11 ms·

Ten seconds of math

248 points by countryqt30 12y ago

mkoryak 12y ago
I thought that maybe the ranking was real.. no its not function getRank(score) { // TODO we should add a real ranking one day var ONE_BARELY_REACHES_THIS_SCORE = 200; return Math.floor(100 * Math.min(Math.E * score / (ONE_BARELY_REACHES_THIS_SCORE * Math.PI), 1)); }
- flares 12y ago
  WTH?? then why release it in the first place.. That's the only crucial step in this whole concept..
  - tuxone 12y ago
    It can't be the crucial step since one could open javascript console and type foo=true;$("#question-answer").bind('keydown', function(){if(foo)$("#question-answer").val(eval($("#question").html()));$("#question-answer").keyup();foo=!foo;});
    - flares 12y ago
      okay.. now so.. what is the crucial step in this whole thing? is it generating random numbers with random operators i between them and evaluating whether the solution given by the user is correct and count the number of correct responses?? By crucial step i meant the logic on how he calculates the percentage of people below.. how it changes when the operators used are changed.(is it dependent on operators in the first place? ) and when the range is changed? etc..
- tankenmate 12y ago
  Indeed somehow I managed to do better than 100% of people with a score of 432; I thought it was a reasonably good result but hardly worthy of 100%.
- bausson 12y ago
  Damn, and I was so proud of my best score.
TrainedMonkey 12y ago
Pretty cool, zombie mode morning with addition only and number limit of 30: "You scored 504. You are better than 100 %" I am sure this will be easily beat by all the caffeinated people pretty soon. Updated: this is actually easier with all the other options enabled because you get easy things like sqrt([4, 16, 25]), x * [0,1], and x / [1, 2] a lot. I was actually over 30 seconds on timer when I hit 18^2 question. "You scored 576. You are better than 100 %" Updated 2: I tried raising number limit to max (1000) and suddenly life on hard mode. I got through 272/16 and 930/31, but third question 127 * 49 killed me. "You scored 64. You are better than 27 %"
- aethertap 12y ago
  333 was also better than 100% for the same settings...
  - tytho 12y ago
    https://github.com/michaeljakob/10-seconds-math/blob/master/js/main.js#L144-L149 https://github.com/michaeljakob/10-seconds-math/blob/master/... No real ranking data is being used in this calculation
    - TrainedMonkey 12y ago
      if (sliderMax > 100) { sliderMax = 100; } score = Math.ceil(numAnswersCorrect * (sliderMax / 10 + numOperatorsEnabled)) Score multiplier and number of operators selected directly influence the score. So setting slider to 10 and enabling all operators gives 7 points per question and increasing slider to a 100 raises that to 16 points per question.
    - tytho 12y ago
      What I meant to way was that you're not being ranked amongst your peers. Saying that you're "better than 100%" or any other percentage is just a result of the assumption that a really good score is 200.
geonik 12y ago
With default settings: You scored 666 You are better than 100 %
- bramgg 12y ago
  I got lower than you after you left this comment with default settings (only addition) and it also reported better than 100%.
- Someone 12y ago
  At default settings, only boredom makes me run out of time. [Actually, waiting a full minute or so for time to run out was too boring, too. I changed settings before that] Addition up to 1000 is reasonably fun, but also feels like it would be doable for a really long time with a physical keyboard and at full attention (I got 3328). That also is a weak point of games like this. IMO, games are good if you can play them without attending to them or when they provide interesting problems. Games with dull problems that require your attention fail. A prime example of the first game type is Tetris; I use to say that your spinal cord can play it. Examples of the second type are Sokoban and (a million times so) DROD (http://en.m.wikipedia.org/wiki/Deadly_Rooms_of_Death http://en.m.wikipedia.org/wiki/Deadly_Rooms_of_Death) With all operations checked and numbers up to 1000, I find I need more time, and scoring seems brutal (only 16 points after 2 or 3 correct amswers?) I also find it a bug that you get subtractions with negative numbers as answers. Finally, is it a bug or a feature that starting a game gets you the same problem and partial answer that the last game finished with? It helps in doing a post-mortem, but can make it really hard to get that first answer right.
sillysaurus3 12y ago
When I was near the end, I pressed backspace to clear my answer, and it wound up navigating me back to HN, wiping out my results. (I hate backspace-to-go-back. It's the worst feature in a browser. Is there a way to turn it off?) This mental math exercise is a cool and fun concept! Good execution.
- minikites 12y ago
  You can in Firefox: http://kb.mozillazine.org/Browser.backspace_action http://kb.mozillazine.org/Browser.backspace_action
- Fishkins 12y ago
  In Chrome I think you can only do this with an extension. I use BackStop.
- JesseAldridge 12y ago
  http://www.chromeextensions.org/appearance-functioning/backspacemeansbackspace/ http://www.chromeextensions.org/appearance-functioning/backs...
- jodrellblank 12y ago
  It's also "the worst" feature in Windows Explorer folder view; when it switched from going up the folder tree to going to the previous folder and throwing an error if that folder doesn't exist anymore.
- rkwz 12y ago
  > I hate backspace-to-go-back. It's the worst feature in a browser. Is there a way to turn it off? I love this feature. Makes browser navigation keyboard friendly. Different strokes for different folks I guess.
  - friendzis 12y ago
    What about [alt]+arrow?
  - bkanber 12y ago
bramgg 12y ago
I crazy love how it auto submits your answers for you, super convenient! My dad made me do similar online mental math exercises when I was younger and I always hated how clicking "next" reduced my time. Does it take into account what your settings were when it reports your score relative to others?
- Zarel 12y ago
  Doesn't pressing Enter generally work? I'm usually surprised by how many people click a button to submit a form.
  - bramgg 12y ago
    This was a long time ago, I'm sure if Enter had worked I would have used it. They could have been using poorly implemented AJAX.
3iak 12y ago
got bored at 855 and let it run out, and it would seem I've bested 100% of you
- deleted 12y ago
  [deleted]
- noiv 12y ago
  Got same result 16 min later, needs floating points :)
laxatives 12y ago
This feels like a lot more than 10 seconds. You tricked me.
Brashman 12y ago
Does it speed up or end eventually? I stored up 150 seconds left before I decided to quit (score of 2529).
- dojo999 12y ago
  For a moment I had the idea it was speeding up, but later on I felt like it was just an illusion. Got to 5661 before stopping.
  - tantaman 12y ago
    yeah... it never ends if you're too fast.. lame...
jhonnycano 12y ago
The number limit should be more granular, or even it would be nice to be able to "pin" one number... i'm thinking of studying times tables for my children! other than that, very nice
- Rambition 12y ago
  Agreed, great tool, would love to be able to set for my kids to focus on certain times tables. Really cool.
danbruc 12y ago
For me there is a set of calculations I can do without thinking and there is a set where it takes several seconds to figure the solution out. No smooth transition. Is it the same for you? If yes, this would make tuning this game pretty hard because it is either to easy or to hard.
- RobertKerans 12y ago
  Yeah, I was sent a link to a similar site yesterday (timed mental arithmetic/algebra), and was thinking exactly the same thing: divided by types, half the problems I could do instantly with almost no thought, but the other half, regardless of how easy, took a few seconds. I noticed that with, for example, multiplication, I have a set of rote-learned answers for calculations that aren't 2, 5 or *10, and if the answer isn't one of those answers, I'll get the closest answer I can remember, and work back/forward from that. It's entirely habit, and I can't stop myself doing it. Algebra as well, I always have a moment where I swap parts of the equation in my head; even if it's utterly simple, there's still a noticeable cognitive step.
- Ntrails 12y ago
  When I turned squares on I hit a wall at 23^2 etc. I can do it, but it's 10 seconds just to do that calc. Basically anything bigger than 14. For the rest it was more about staring at the numpad (which I never use) and typing in my answer. If I typo'd I lost several seconds as I'd not have a finger on backspace :(
  - flurie 12y ago
    Squares are actually pretty easy with a mental math trick. n^x = (n-m)(n+m) + m^2 so for 23: 23^2 = 20*26 + 9 = 529
skellystudios 12y ago
Just for anyone who feels pleased with their mental maths and thinks they might be able to take on their calculator head-to-head: window.setInterval(function(){$('#question-answer').val(eval($('#question').html().replace("×","").replace("÷","/").replace(/(.)²/,"Math.pow($1,2)").replace(/√(.*)/,"Math.sqrt($1)"))).trigger("keyup")},10)
- bengali3 12y ago
  your paste lost an asterisk * in the first replace statement
SCdF 12y ago
OT: I ended up being mostly fascinated with the FB and Twitter share buttons
- pbhjpbhj 12y ago
  Why? I can't see anything interesting about them, they seem stock?
  - SCdF 12y ago
    Play the game, and then let it fail so you lose, then look at the FB and Twitter share buttons under your score :-)
_RPM 12y ago
This is pretty cool but, is it a game? I can't see how solving math problems under a time limit can be useful for anything besides a math exam or some other academic test.
- kachnuv_ocasek 12y ago
  A long time ago, I read an article concerning mathematical problems and how solving them improves (probably short term) intelligence. It turned out that simple arithmetic was the most useful. Of course, I can't find the source right now.
- ajkjk 12y ago
  My experience has been that mental math training, while not directly useful, generally seems to improve the way my brain works and enhances my analytic thinking. This effect is a lot more tangible with longer, multi-step problems. In college (physics major) I made a point of doing every integral in my head if I could, and over time I found that my mental 'scratch space' seemed to be getting longer - that I could hold more in my short-term memory at once. I've also observed that being a person who is 'good at math' approximately correlates with being a person who does math in your head. [Related observation: that students strongly segregate into "good at math" vs not, as though many people are completely incapable of a mode of thought that comes naturally to others. I think it's trainable, and people who never do any math, especially in their heads, are specifically not training it.] These are entirely anecdotal and I'd love to find more concrete data, but, right now I would absolutely vouch for mental math training.
  - j2kun 12y ago
    General problem solving and critical thinking is good mental training. Timed arithmetic drills are neither, and I really should hope that arithmetic doesn't count as "critical thinking" for the majority of the audience on HN.
    - Qwertious 12y ago
      I have to agree - for all the talk of "mental training", is there any actual evidence that arithmetic drills will actually help with problem-solving and critical-thinking?
adeptus 12y ago
Was not disappointed. Was half expecting a 3 page long article about some epiphany over 10 seconds of math contemplation.
tomp 12y ago
My score: 4785 :) (all options, number limit = 50)
rlvesco7 12y ago
I've played with many of these. And this one is pretty good. One thing that I'd like to see is a "verbal" option in these types of apps. I have trouble "hearing" math and keeping it in my head. I envision an app speaking the problem, then you have to type in the answer. It requires both math and keeping the problem in your head. Lastly, a verbal or speaking option maps to many real world scenarios.
- eric_bullington 12y ago
  >I have trouble "hearing" math and keeping it in my head. I have the exact same problem. Interestingly, it's a problem for me both in my native language and in several other languages I learned to fluency. So clearly, the "hears numbers" part of my brain is deficient. I've actually practiced to try to overcome this, and made no progress. On the other hand, I'm quite good at visual calculations, and also at remembering numbers when I see them. So if I bother writing down a phone number, I can easily remember it for a long time. But hearing it? Nothing.
- throwathrowaway 12y ago
  http://ccccnews.herokuapp.com/ http://ccccnews.herokuapp.com/ Use the numpad. If you don't care about the setting: 1. Click "Play game" 2. Press 2, Enter, Star once it loads. Make 24. Enter the two intermediate results. Numpad plus repeats the question. I don't know if this is a good place to start if you have trouble hearing but might be fun for practice anyway.
refrigerator 12y ago
Nice! I made something similar a while ago - http://www.speedsums.com http://www.speedsums.com :)
- yror10 12y ago
  I instantly remembered speedsums once opening this site there. Went to the comments to check to see if it was referenced. Boom.
- amadeusw 12y ago
  I like how it remembers your worst answer and reminds you what's the correct answer! The victory animation was a bit terrifying though, like one of those "stare at the screen" pranks :) Cheers
sleepychu 12y ago
http://imgur.com/J2CNCmV http://imgur.com/J2CNCmV ...
fletchowns 12y ago
I wonder if there would be any difference in the results if the numbers were stacked vertically instead of horizontally
bvanslyke 12y ago
Noticed some fun SEO hacking at the bottom of the page: <p class="hardly-visible">puzzles calculate formula mathematics maths decimal number calculating mathematician multiply measurement probability equation division measure homework units word problem solve converting resources tessellation anxiety math problem problems convert unit ratio number trigonometry perimeter divide mental multiplication calculus math quadratic triangle teselation problems pi change equations homeschool fraction tesellation converter maths problems fractions conversion math prime mathmagic Theorem calculator percent magic homework fractol volume math math tesselation math math math mathematical statistic unit geometry math polygon square math pre-algebra algebra word statistics games area math Pythagorean fractal history trapezoid maths conversion circle numbers circle </p>
- troels 12y ago
  They should remove that. It'll get them smacked by the google spam team eventually.
  - bramgg 12y ago
    If not already... You really shouldn't do stuff like that. SEO 101.
    - camillomiller 12y ago
      Yeah, and I don't understand why people still do that. It may work. For like a couple of weeks, before you get banned forever. It's even easier to do stuff the right way, especially in a one page design. Just leave the logic up above. Then put a long, well written text about math, the importance of brain exercise and a description of the game with well divided H1/H2 headings, below it. Here's all the SEO you need. The link from HN and all the sites that scrape it will do the rest.
  - mattbreeden 12y ago
    https://github.com/michaeljakob/10-seconds-math https://github.com/michaeljakob/10-seconds-math you can submit a PR to remove it
deleted 12y ago
[deleted]
johnlopez 12y ago
It'd be pretty cool if this actually had leaderboards, perhaps one leaderboard per set of options, limited to clusters so as to minimize the amount of leaderboards. Such as "arithmetic, multiplication+division, arithmetic and mutliplication+division, free for all" Was pretty upset to see that the result for scoring 5xx was the same as my next run of 7920
- codingdave 12y ago
  A leaderboard wouldn't be meaningful -- Client-side code isn't secure, and people could set scores to whatever they like. Or, just for fun, I played with the page a bit via dev tools, added in a script to automatically calculate the answer, put it in the input, and trigger the keyup event to run their submit function... worked great. There is nothing wrong with client-side tools. I have a few on my site that get decent usage. But unless you put some security and validation on the server-side, any data coming back is not trustworthy.
S4M 12y ago
It's boring at some point. You should make a countdown instead: you have, say, 1 minute to answer as much questions as you can (with an possible skip button).
- matthewwiese 12y ago
  At first I actually thought that's what the game would be. I was pleasantly surprised that it was more like juggling, by the end when I had 1-2 seconds per problem, I was far more interested. Something about keeping up the "combo" but testing my arithmetic was quite pleasurable.
tagawa 12y ago
I got redirected to the Google Play store. If I'm on Android why can't I use the website like everyone else? Please don't assume I want to install an app.
- Kenan 12y ago
  I also got redirected... I'm on Windows Phone.
0x0 12y ago
"You scored: 315. You are better than 100%". Why do I think their countdown timer needs some work on MobileSafari? :)
mtam 12y ago
After going for several minutes I gave up. In addition to a leader board, it needs to: - Have a time limit and see who can get the most calculations done on that fixed time - or, have a fixed number of calculations and see how fast people can answer them - or, it could get faster as you progress The calculation of the "you are better than X%" needs to be fixed because everybody in my office was better than 100%
- johnlopez 12y ago
  I was thinking maybe instead of a leaderboard, graphs/analysis of raw data would be very cool, such as accuracy and answers per second and total score, and how those stats match up with the rest of the people who have played
porter 12y ago
For me there are certain mental calculations that take longer to process than others. 2 + 2 is super easy. 7+8 is not as immediate. I need a program like this that learns which calculation take me longer, even if it's just slightly longer, and then drills and drills my weak points over and over again. That would be a real mental math trainer.
- sirsar 12y ago
  With a bit of tweaking, Anki [0] or another Spaced Repetition Software program will do just that. You can configure it to categorize your answers by how fast you answered them. Then it will make the easy ones less frequent. I used it to memorize the times table up to 20x20. [0] http://ankisrs.net http://ankisrs.net
  - pbhjpbhj 12y ago
    Is that stack available for times-tables ready to install and use, if not can you share it? Thanks.
    - sirsar 12y ago
      I just generated a text file with a quick shell script and imported the output into Anki. I have neither anymore, but the text file just looked like 1,1,1 1,2,2 2,1,1 2,2,4 3,1,3 ...etc
vojfox 12y ago
math score: 243 In just 10 seconds http://mental-math-trainer.com http://mental-math-trainer.com i know the guy who made this game for iOS https://itunes.apple.com/us/app/brain-tuner-free/id391266485?mt=8 https://itunes.apple.com/us/app/brain-tuner-free/id391266485... https://itunes.apple.com/us/app/brain-tuner-x/id287360582?mt=8 https://itunes.apple.com/us/app/brain-tuner-x/id287360582?mt...
aaronetz 12y ago
I actually made a mental math game for Android not long ago. The concept is different though - it's about choosing the operations to reach a target number. I would appreciate any feedback! https://play.google.com/store/apps/details?id=com.woodencloset.mathmachine.android https://play.google.com/store/apps/details?id=com.woodenclos...
- pbhjpbhj 12y ago
  I have this on my phone, my 5 and 9 year olds like it! I find the hard level pretty hard - it would be good IMO if you could change the mode to include negatives (maybe roots and squares [+other powers?], like here) and to expand the number range to. I seem to remember someone mentioning (probably on here) that they played a mental maths game where you had to give an operation on a number, you didn't say the answer but the next person had to add an operation, there was always a range (age adjusted) that the answer had to fit within: was that game the inspiration or was it just a novel idea for you? Like the game anyway, thanks.
  - aaronetz 12y ago
    Thanks for the feedback! If the hard level is pretty hard, wouldn't adding more operations make it even harder? I kept the number range small because I felt it would be too hard to do mentally otherwise, but I'm definitely open to extending it. The idea was novel for me but I was quite certain it has been done before in one way or another.
    - pbhjpbhj 12y ago
      It would probably make the hard level even harder (assuming unique solutions then definitely) but for the lower levels it would provide a wide range of play styles and so more replayability - I'd probably be more inclined to play intermediate with wider ranges and/or other operations than to play hard in "simple" mode.
    - deleted 12y ago
      [deleted]
hf 12y ago
On Debian (and, I'm sure other distributions of GNU/Linux) the 'bsdgames' package contains a simple program called 'arithmetic' which poses similar challenges, albeit reduced to the most elementary operations: addition and substraction. Call as arithmetic -o '+-x/' in order to add multiplication and division. I find it a handy supplement to 'gtypist' in order to train touch-typing of numbers. On a side-note: I'm surprised at how scarce such software is - pitiful as it may be. But then, the advancement of the human intellect isn't at the forefront of our cultural conscious, is it?
bbcbasic 12y ago
Good game, it has that silly 'flappy bird' style appeal that it is difficult to keep going - they should reduce the additional time given per question to go more in that direction.
Scarbutt 12y ago
Where can one learn about techniques for getting faster at mental arithmetic?
lukencode 12y ago
A mate of mine is behind - http://numbertap.com/ http://numbertap.com/ Similar concept but with cross platform multiplayer.
j2kun 12y ago
Too bad it's things like this that make average people think math is little more than arithmetic.
- Retra 12y ago
  I'll quote one of my math professors: "At this level, nobody knows how to subtract!"
chdir 12y ago
Square roots should be improved, just ranges from squares of 0 to 6.
basman 12y ago
352 with all options and limit 1000. Anyone do better? :)
userbinator 12y ago
Scored 47232 before giving up... For those who are still struggling with mental arithmetic, or kids just learning, this seems like it would be a great way to practice --- there is a a certain addictive quality to it, like "flappy bird".
unholycrab 12y ago
As a farmer, I am deeply offended by this game.
ilitirit 12y ago
People should start differentiating between mathematics and arithmetic.
- tempestn 12y ago
  Arithmetic is a (small but fundamental) subset of mathematics. I don't see anything wrong with the title.
  - dsfsdfd 12y ago
    Arithmetic != Mathematics just as Typing != Programming Sure, typing is a useful skill, it's part of programming, but is it programming? - no of course not. In fact it's insulting to programmers to make the confusion. It's the same with those of us who have taken the time to get good at mathematics - it's not arithmetic. Being good at arithmetic does not mean you are good at math, being good at math does not make you good at arithmetic. This confusion is especially detrimental to children, many of whom will be put of mathematics because they equate it with the wrote learning and peculiar mental gymnastics of arithmetic, rather than what it is: An exploration of the beautiful and fundamental symmetries that emerge from structure and process.
    - dghf 12y ago
      Yes, but arithmetics is a branch of maths, whereas typing is not a branch of programming. Maybe they plan to extend the site to include trig, algebra, calculus, etc. problems?
      - dsfsdfd 12y ago
        Not really. Mental arithmetic is the ability to move numbers around in your head, it really is equivalent to being able to type as a programmer. Mental arithmetic is to number theory as being able to type is to programming. That you do not understand this, shows that you too have been damaged by the standard teaching of maths within education - pre university level.
lpman 12y ago
Something similar on android: https://play.google.com/store/apps/details?id=mental.care.activities https://play.google.com/store/apps/details?id=mental.care.ac... I haven't updated it a while, but feel free to try it
kissickas 12y ago
This just showed me the need for a numeric keypad. Half of the time I spent was looking for the right keys or correcting mistypes - normally I think I'm pretty good getting $ and * every time without looking. I think the change in performance here has something to do with never returning to the home row; I'm just completely lost on laptops.
kriro 12y ago
Minor bug I noticed: When the timer hit zero it went back up to 1 second and then down to 0. FF 33.1 on Mac if that matters.
k-mcgrady 12y ago
I like this. Duolingo does something similar for language practice. After you've completed lessons you can do a timed practice session where it will ask you to translate words you've already learnt. It counts down and the quicker you get it correct the more time gets added to your countdown.
akhilkohli2005 12y ago
Champion of addition setInterval(function() {document.getElementById('question-answer').value = Number(document.getElementById('question').innerHTML.split(' ')[0]) + Number(document.getElementById('question').innerHTML.split(' ')[2]); $('#question-answer').trigger(jQuery.Event( 'keyup', 16 ));},500)
bybak 12y ago
In my opinion giving that much freedom (all those settings) to user is not good and ruins the gameplay. I'd prefer such game to start simple and increase difficulty by itself. I find this one almost perfect: http://games.usvsth3m.com/maths/ http://games.usvsth3m.com/maths/ although it lacks more levels.
nojvek 12y ago
Suck at arithmentic. But this took me 20 seconds to write. setInterval(function(){ $("#question-answer").val(eval($("#question").text())).trigger("keyup") }, 2001);
shenoyroopesh 12y ago
And here's a reverse-math extension. (and No funny SEO) :) I think clicking is easier than typing. http://reverse-math.makkajai.com http://reverse-math.makkajai.com
countryqt30 12y ago
New features! - difficulty increases over time - motivations on correct answers - slightly adjusted question difficulty - sliders are disabled while scoring :) Feel free to test it and let me know :D http://www.mental-math-trainer.com/ http://www.mental-math-trainer.com/

248 points by countryqt30 12y ago

I thought that maybe the ranking was real.. no its not function getRank(score) { // TODO we should add a real ranking one day var ONE_BARELY_REACHES_THIS_SCORE = 200; return Math.floor(100 * Math.min(Math.E * score / (ONE_BARELY_REACHES_THIS_SCORE * Math.PI), 1)); }

flares 12y ago
WTH?? then why release it in the first place.. That's the only crucial step in this whole concept..
- tuxone 12y ago
  It can't be the crucial step since one could open javascript console and type foo=true;$("#question-answer").bind('keydown', function(){if(foo)$("#question-answer").val(eval($("#question").html()));$("#question-answer").keyup();foo=!foo;});
  - flares 12y ago
    okay.. now so.. what is the crucial step in this whole thing? is it generating random numbers with random operators i between them and evaluating whether the solution given by the user is correct and count the number of correct responses?? By crucial step i meant the logic on how he calculates the percentage of people below.. how it changes when the operators used are changed.(is it dependent on operators in the first place? ) and when the range is changed? etc..
tankenmate 12y ago
Indeed somehow I managed to do better than 100% of people with a score of 432; I thought it was a reasonably good result but hardly worthy of 100%.
bausson 12y ago
Damn, and I was so proud of my best score.

TrainedMonkey 12y ago

Pretty cool, zombie mode morning with addition only and number limit of 30: "You scored 504. You are better than 100 %" I am sure this will be easily beat by all the caffeinated people pretty soon. Updated: this is actually easier with all the other options enabled because you get easy things like sqrt([4, 16, 25]), x * [0,1], and x / [1, 2] a lot. I was actually over 30 seconds on timer when I hit 18^2 question. "You scored 576. You are better than 100 %" Updated 2: I tried raising number limit to max (1000) and suddenly life on hard mode. I got through 272/16 and 930/31, but third question 127 * 49 killed me. "You scored 64. You are better than 27 %"

aethertap 12y ago
333 was also better than 100% for the same settings...
- tytho 12y ago
  https://github.com/michaeljakob/10-seconds-math/blob/master/js/main.js#L144-L149 https://github.com/michaeljakob/10-seconds-math/blob/master/... No real ranking data is being used in this calculation
  - TrainedMonkey 12y ago
    if (sliderMax > 100) { sliderMax = 100; } score = Math.ceil(numAnswersCorrect * (sliderMax / 10 + numOperatorsEnabled)) Score multiplier and number of operators selected directly influence the score. So setting slider to 10 and enabling all operators gives 7 points per question and increasing slider to a 100 raises that to 16 points per question.
  - tytho 12y ago
    What I meant to way was that you're not being ranked amongst your peers. Saying that you're "better than 100%" or any other percentage is just a result of the assumption that a really good score is 200.

geonik 12y ago

With default settings: You scored 666 You are better than 100 %

bramgg 12y ago
I got lower than you after you left this comment with default settings (only addition) and it also reported better than 100%.
Someone 12y ago
At default settings, only boredom makes me run out of time. [Actually, waiting a full minute or so for time to run out was too boring, too. I changed settings before that] Addition up to 1000 is reasonably fun, but also feels like it would be doable for a really long time with a physical keyboard and at full attention (I got 3328). That also is a weak point of games like this. IMO, games are good if you can play them without attending to them or when they provide interesting problems. Games with dull problems that require your attention fail. A prime example of the first game type is Tetris; I use to say that your spinal cord can play it. Examples of the second type are Sokoban and (a million times so) DROD (http://en.m.wikipedia.org/wiki/Deadly_Rooms_of_Death http://en.m.wikipedia.org/wiki/Deadly_Rooms_of_Death) With all operations checked and numbers up to 1000, I find I need more time, and scoring seems brutal (only 16 points after 2 or 3 correct amswers?) I also find it a bug that you get subtractions with negative numbers as answers. Finally, is it a bug or a feature that starting a game gets you the same problem and partial answer that the last game finished with? It helps in doing a post-mortem, but can make it really hard to get that first answer right.

sillysaurus3 12y ago

When I was near the end, I pressed backspace to clear my answer, and it wound up navigating me back to HN, wiping out my results. (I hate backspace-to-go-back. It's the worst feature in a browser. Is there a way to turn it off?) This mental math exercise is a cool and fun concept! Good execution.

minikites 12y ago
You can in Firefox: http://kb.mozillazine.org/Browser.backspace_action http://kb.mozillazine.org/Browser.backspace_action
Fishkins 12y ago
In Chrome I think you can only do this with an extension. I use BackStop.
JesseAldridge 12y ago
http://www.chromeextensions.org/appearance-functioning/backspacemeansbackspace/ http://www.chromeextensions.org/appearance-functioning/backs...
jodrellblank 12y ago
It's also "the worst" feature in Windows Explorer folder view; when it switched from going up the folder tree to going to the previous folder and throwing an error if that folder doesn't exist anymore.
rkwz 12y ago
> I hate backspace-to-go-back. It's the worst feature in a browser. Is there a way to turn it off? I love this feature. Makes browser navigation keyboard friendly. Different strokes for different folks I guess.
- friendzis 12y ago
  What about [alt]+arrow?
- bkanber 12y ago

bramgg 12y ago

I crazy love how it auto submits your answers for you, super convenient! My dad made me do similar online mental math exercises when I was younger and I always hated how clicking "next" reduced my time. Does it take into account what your settings were when it reports your score relative to others?

Zarel 12y ago
Doesn't pressing Enter generally work? I'm usually surprised by how many people click a button to submit a form.
- bramgg 12y ago
  This was a long time ago, I'm sure if Enter had worked I would have used it. They could have been using poorly implemented AJAX.

3iak 12y ago

got bored at 855 and let it run out, and it would seem I've bested 100% of you

deleted 12y ago
[deleted]
noiv 12y ago
Got same result 16 min later, needs floating points :)

laxatives 12y ago

This feels like a lot more than 10 seconds. You tricked me.

Brashman 12y ago

Does it speed up or end eventually? I stored up 150 seconds left before I decided to quit (score of 2529).

dojo999 12y ago
For a moment I had the idea it was speeding up, but later on I felt like it was just an illusion. Got to 5661 before stopping.
- tantaman 12y ago
  yeah... it never ends if you're too fast.. lame...

jhonnycano 12y ago

The number limit should be more granular, or even it would be nice to be able to "pin" one number... i'm thinking of studying times tables for my children! other than that, very nice

Rambition 12y ago
Agreed, great tool, would love to be able to set for my kids to focus on certain times tables. Really cool.

danbruc 12y ago

For me there is a set of calculations I can do without thinking and there is a set where it takes several seconds to figure the solution out. No smooth transition. Is it the same for you? If yes, this would make tuning this game pretty hard because it is either to easy or to hard.

RobertKerans 12y ago
Yeah, I was sent a link to a similar site yesterday (timed mental arithmetic/algebra), and was thinking exactly the same thing: divided by types, half the problems I could do instantly with almost no thought, but the other half, regardless of how easy, took a few seconds. I noticed that with, for example, multiplication, I have a set of rote-learned answers for calculations that aren't 2, 5 or *10, and if the answer isn't one of those answers, I'll get the closest answer I can remember, and work back/forward from that. It's entirely habit, and I can't stop myself doing it. Algebra as well, I always have a moment where I swap parts of the equation in my head; even if it's utterly simple, there's still a noticeable cognitive step.
Ntrails 12y ago
When I turned squares on I hit a wall at 23^2 etc. I can do it, but it's 10 seconds just to do that calc. Basically anything bigger than 14. For the rest it was more about staring at the numpad (which I never use) and typing in my answer. If I typo'd I lost several seconds as I'd not have a finger on backspace :(
- flurie 12y ago
  Squares are actually pretty easy with a mental math trick. n^x = (n-m)(n+m) + m^2 so for 23: 23^2 = 20*26 + 9 = 529

skellystudios 12y ago

Just for anyone who feels pleased with their mental maths and thinks they might be able to take on their calculator head-to-head: window.setInterval(function(){$('#question-answer').val(eval($('#question').html().replace("×","").replace("÷","/").replace(/(.)²/,"Math.pow($1,2)").replace(/√(.*)/,"Math.sqrt($1)"))).trigger("keyup")},10)

bengali3 12y ago
your paste lost an asterisk * in the first replace statement

SCdF 12y ago

OT: I ended up being mostly fascinated with the FB and Twitter share buttons

pbhjpbhj 12y ago
Why? I can't see anything interesting about them, they seem stock?
- SCdF 12y ago
  Play the game, and then let it fail so you lose, then look at the FB and Twitter share buttons under your score :-)

_RPM 12y ago

This is pretty cool but, is it a game? I can't see how solving math problems under a time limit can be useful for anything besides a math exam or some other academic test.

kachnuv_ocasek 12y ago
A long time ago, I read an article concerning mathematical problems and how solving them improves (probably short term) intelligence. It turned out that simple arithmetic was the most useful. Of course, I can't find the source right now.
ajkjk 12y ago
My experience has been that mental math training, while not directly useful, generally seems to improve the way my brain works and enhances my analytic thinking. This effect is a lot more tangible with longer, multi-step problems. In college (physics major) I made a point of doing every integral in my head if I could, and over time I found that my mental 'scratch space' seemed to be getting longer - that I could hold more in my short-term memory at once. I've also observed that being a person who is 'good at math' approximately correlates with being a person who does math in your head. [Related observation: that students strongly segregate into "good at math" vs not, as though many people are completely incapable of a mode of thought that comes naturally to others. I think it's trainable, and people who never do any math, especially in their heads, are specifically not training it.] These are entirely anecdotal and I'd love to find more concrete data, but, right now I would absolutely vouch for mental math training.
- j2kun 12y ago
  General problem solving and critical thinking is good mental training. Timed arithmetic drills are neither, and I really should hope that arithmetic doesn't count as "critical thinking" for the majority of the audience on HN.
  - Qwertious 12y ago
    I have to agree - for all the talk of "mental training", is there any actual evidence that arithmetic drills will actually help with problem-solving and critical-thinking?

adeptus 12y ago

Was not disappointed. Was half expecting a 3 page long article about some epiphany over 10 seconds of math contemplation.

tomp 12y ago

My score: 4785 :) (all options, number limit = 50)

rlvesco7 12y ago

I've played with many of these. And this one is pretty good. One thing that I'd like to see is a "verbal" option in these types of apps. I have trouble "hearing" math and keeping it in my head. I envision an app speaking the problem, then you have to type in the answer. It requires both math and keeping the problem in your head. Lastly, a verbal or speaking option maps to many real world scenarios.

eric_bullington 12y ago
>I have trouble "hearing" math and keeping it in my head. I have the exact same problem. Interestingly, it's a problem for me both in my native language and in several other languages I learned to fluency. So clearly, the "hears numbers" part of my brain is deficient. I've actually practiced to try to overcome this, and made no progress. On the other hand, I'm quite good at visual calculations, and also at remembering numbers when I see them. So if I bother writing down a phone number, I can easily remember it for a long time. But hearing it? Nothing.
throwathrowaway 12y ago
http://ccccnews.herokuapp.com/ http://ccccnews.herokuapp.com/ Use the numpad. If you don't care about the setting: 1. Click "Play game" 2. Press 2, Enter, Star once it loads. Make 24. Enter the two intermediate results. Numpad plus repeats the question. I don't know if this is a good place to start if you have trouble hearing but might be fun for practice anyway.

refrigerator 12y ago

Nice! I made something similar a while ago - http://www.speedsums.com http://www.speedsums.com :)

yror10 12y ago
I instantly remembered speedsums once opening this site there. Went to the comments to check to see if it was referenced. Boom.
amadeusw 12y ago
I like how it remembers your worst answer and reminds you what's the correct answer! The victory animation was a bit terrifying though, like one of those "stare at the screen" pranks :) Cheers

sleepychu 12y ago

http://imgur.com/J2CNCmV http://imgur.com/J2CNCmV ...

fletchowns 12y ago

I wonder if there would be any difference in the results if the numbers were stacked vertically instead of horizontally

bvanslyke 12y ago

Noticed some fun SEO hacking at the bottom of the page: <p class="hardly-visible">puzzles calculate formula mathematics maths decimal number calculating mathematician multiply measurement probability equation division measure homework units word problem solve converting resources tessellation anxiety math problem problems convert unit ratio number trigonometry perimeter divide mental multiplication calculus math quadratic triangle teselation problems pi change equations homeschool fraction tesellation converter maths problems fractions conversion math prime mathmagic Theorem calculator percent magic homework fractol volume math math tesselation math math math mathematical statistic unit geometry math polygon square math pre-algebra algebra word statistics games area math Pythagorean fractal history trapezoid maths conversion circle numbers circle </p>

troels 12y ago
They should remove that. It'll get them smacked by the google spam team eventually.
- bramgg 12y ago
  If not already... You really shouldn't do stuff like that. SEO 101.
  - camillomiller 12y ago
    Yeah, and I don't understand why people still do that. It may work. For like a couple of weeks, before you get banned forever. It's even easier to do stuff the right way, especially in a one page design. Just leave the logic up above. Then put a long, well written text about math, the importance of brain exercise and a description of the game with well divided H1/H2 headings, below it. Here's all the SEO you need. The link from HN and all the sites that scrape it will do the rest.
- mattbreeden 12y ago
  https://github.com/michaeljakob/10-seconds-math https://github.com/michaeljakob/10-seconds-math you can submit a PR to remove it

deleted 12y ago

[deleted]

johnlopez 12y ago

It'd be pretty cool if this actually had leaderboards, perhaps one leaderboard per set of options, limited to clusters so as to minimize the amount of leaderboards. Such as "arithmetic, multiplication+division, arithmetic and mutliplication+division, free for all" Was pretty upset to see that the result for scoring 5xx was the same as my next run of 7920

codingdave 12y ago
A leaderboard wouldn't be meaningful -- Client-side code isn't secure, and people could set scores to whatever they like. Or, just for fun, I played with the page a bit via dev tools, added in a script to automatically calculate the answer, put it in the input, and trigger the keyup event to run their submit function... worked great. There is nothing wrong with client-side tools. I have a few on my site that get decent usage. But unless you put some security and validation on the server-side, any data coming back is not trustworthy.

S4M 12y ago

It's boring at some point. You should make a countdown instead: you have, say, 1 minute to answer as much questions as you can (with an possible skip button).

matthewwiese 12y ago
At first I actually thought that's what the game would be. I was pleasantly surprised that it was more like juggling, by the end when I had 1-2 seconds per problem, I was far more interested. Something about keeping up the "combo" but testing my arithmetic was quite pleasurable.

tagawa 12y ago

I got redirected to the Google Play store. If I'm on Android why can't I use the website like everyone else? Please don't assume I want to install an app.

Kenan 12y ago
I also got redirected... I'm on Windows Phone.

0x0 12y ago

"You scored: 315. You are better than 100%". Why do I think their countdown timer needs some work on MobileSafari? :)

mtam 12y ago

After going for several minutes I gave up. In addition to a leader board, it needs to: - Have a time limit and see who can get the most calculations done on that fixed time - or, have a fixed number of calculations and see how fast people can answer them - or, it could get faster as you progress The calculation of the "you are better than X%" needs to be fixed because everybody in my office was better than 100%

johnlopez 12y ago
I was thinking maybe instead of a leaderboard, graphs/analysis of raw data would be very cool, such as accuracy and answers per second and total score, and how those stats match up with the rest of the people who have played

porter 12y ago

For me there are certain mental calculations that take longer to process than others. 2 + 2 is super easy. 7+8 is not as immediate. I need a program like this that learns which calculation take me longer, even if it's just slightly longer, and then drills and drills my weak points over and over again. That would be a real mental math trainer.

sirsar 12y ago
With a bit of tweaking, Anki [0] or another Spaced Repetition Software program will do just that. You can configure it to categorize your answers by how fast you answered them. Then it will make the easy ones less frequent. I used it to memorize the times table up to 20x20. [0] http://ankisrs.net http://ankisrs.net
- pbhjpbhj 12y ago
  Is that stack available for times-tables ready to install and use, if not can you share it? Thanks.
  - sirsar 12y ago
    I just generated a text file with a quick shell script and imported the output into Anki. I have neither anymore, but the text file just looked like 1,1,1 1,2,2 2,1,1 2,2,4 3,1,3 ...etc

vojfox 12y ago

math score: 243 In just 10 seconds http://mental-math-trainer.com http://mental-math-trainer.com i know the guy who made this game for iOS https://itunes.apple.com/us/app/brain-tuner-free/id391266485?mt=8 https://itunes.apple.com/us/app/brain-tuner-free/id391266485... https://itunes.apple.com/us/app/brain-tuner-x/id287360582?mt=8 https://itunes.apple.com/us/app/brain-tuner-x/id287360582?mt...

aaronetz 12y ago

I actually made a mental math game for Android not long ago. The concept is different though - it's about choosing the operations to reach a target number. I would appreciate any feedback! https://play.google.com/store/apps/details?id=com.woodencloset.mathmachine.android https://play.google.com/store/apps/details?id=com.woodenclos...

pbhjpbhj 12y ago
I have this on my phone, my 5 and 9 year olds like it! I find the hard level pretty hard - it would be good IMO if you could change the mode to include negatives (maybe roots and squares [+other powers?], like here) and to expand the number range to. I seem to remember someone mentioning (probably on here) that they played a mental maths game where you had to give an operation on a number, you didn't say the answer but the next person had to add an operation, there was always a range (age adjusted) that the answer had to fit within: was that game the inspiration or was it just a novel idea for you? Like the game anyway, thanks.
- aaronetz 12y ago
  Thanks for the feedback! If the hard level is pretty hard, wouldn't adding more operations make it even harder? I kept the number range small because I felt it would be too hard to do mentally otherwise, but I'm definitely open to extending it. The idea was novel for me but I was quite certain it has been done before in one way or another.
  - pbhjpbhj 12y ago
    It would probably make the hard level even harder (assuming unique solutions then definitely) but for the lower levels it would provide a wide range of play styles and so more replayability - I'd probably be more inclined to play intermediate with wider ranges and/or other operations than to play hard in "simple" mode.
  - deleted 12y ago
    [deleted]

hf 12y ago

On Debian (and, I'm sure other distributions of GNU/Linux) the 'bsdgames' package contains a simple program called 'arithmetic' which poses similar challenges, albeit reduced to the most elementary operations: addition and substraction. Call as arithmetic -o '+-x/' in order to add multiplication and division. I find it a handy supplement to 'gtypist' in order to train touch-typing of numbers. On a side-note: I'm surprised at how scarce such software is - pitiful as it may be. But then, the advancement of the human intellect isn't at the forefront of our cultural conscious, is it?

bbcbasic 12y ago

Good game, it has that silly 'flappy bird' style appeal that it is difficult to keep going - they should reduce the additional time given per question to go more in that direction.

Scarbutt 12y ago

Where can one learn about techniques for getting faster at mental arithmetic?

lukencode 12y ago

A mate of mine is behind - http://numbertap.com/ http://numbertap.com/ Similar concept but with cross platform multiplayer.

j2kun 12y ago

Too bad it's things like this that make average people think math is little more than arithmetic.

Retra 12y ago
I'll quote one of my math professors: "At this level, nobody knows how to subtract!"

chdir 12y ago

Square roots should be improved, just ranges from squares of 0 to 6.

basman 12y ago

352 with all options and limit 1000. Anyone do better? :)

userbinator 12y ago

Scored 47232 before giving up... For those who are still struggling with mental arithmetic, or kids just learning, this seems like it would be a great way to practice --- there is a a certain addictive quality to it, like "flappy bird".

unholycrab 12y ago

As a farmer, I am deeply offended by this game.

ilitirit 12y ago

People should start differentiating between mathematics and arithmetic.

tempestn 12y ago
Arithmetic is a (small but fundamental) subset of mathematics. I don't see anything wrong with the title.
- dsfsdfd 12y ago
  Arithmetic != Mathematics just as Typing != Programming Sure, typing is a useful skill, it's part of programming, but is it programming? - no of course not. In fact it's insulting to programmers to make the confusion. It's the same with those of us who have taken the time to get good at mathematics - it's not arithmetic. Being good at arithmetic does not mean you are good at math, being good at math does not make you good at arithmetic. This confusion is especially detrimental to children, many of whom will be put of mathematics because they equate it with the wrote learning and peculiar mental gymnastics of arithmetic, rather than what it is: An exploration of the beautiful and fundamental symmetries that emerge from structure and process.
  - dghf 12y ago
    Yes, but arithmetics is a branch of maths, whereas typing is not a branch of programming. Maybe they plan to extend the site to include trig, algebra, calculus, etc. problems?
    - dsfsdfd 12y ago
      Not really. Mental arithmetic is the ability to move numbers around in your head, it really is equivalent to being able to type as a programmer. Mental arithmetic is to number theory as being able to type is to programming. That you do not understand this, shows that you too have been damaged by the standard teaching of maths within education - pre university level.

lpman 12y ago

Something similar on android: https://play.google.com/store/apps/details?id=mental.care.activities https://play.google.com/store/apps/details?id=mental.care.ac... I haven't updated it a while, but feel free to try it

kissickas 12y ago

This just showed me the need for a numeric keypad. Half of the time I spent was looking for the right keys or correcting mistypes - normally I think I'm pretty good getting $ and * every time without looking. I think the change in performance here has something to do with never returning to the home row; I'm just completely lost on laptops.

kriro 12y ago

Minor bug I noticed: When the timer hit zero it went back up to 1 second and then down to 0. FF 33.1 on Mac if that matters.

k-mcgrady 12y ago

I like this. Duolingo does something similar for language practice. After you've completed lessons you can do a timed practice session where it will ask you to translate words you've already learnt. It counts down and the quicker you get it correct the more time gets added to your countdown.

akhilkohli2005 12y ago

Champion of addition setInterval(function() {document.getElementById('question-answer').value = Number(document.getElementById('question').innerHTML.split(' ')[0]) + Number(document.getElementById('question').innerHTML.split(' ')[2]); $('#question-answer').trigger(jQuery.Event( 'keyup', 16 ));},500)

bybak 12y ago

In my opinion giving that much freedom (all those settings) to user is not good and ruins the gameplay. I'd prefer such game to start simple and increase difficulty by itself. I find this one almost perfect: http://games.usvsth3m.com/maths/ http://games.usvsth3m.com/maths/ although it lacks more levels.

nojvek 12y ago

Suck at arithmentic. But this took me 20 seconds to write. setInterval(function(){ $("#question-answer").val(eval($("#question").text())).trigger("keyup") }, 2001);

shenoyroopesh 12y ago

And here's a reverse-math extension. (and No funny SEO) :) I think clicking is easier than typing. http://reverse-math.makkajai.com http://reverse-math.makkajai.com

countryqt30 12y ago

New features! - difficulty increases over time - motivations on correct answers - slightly adjusted question difficulty - sliders are disabled while scoring :) Feel free to test it and let me know :D http://www.mental-math-trainer.com/ http://www.mental-math-trainer.com/