4 ms·
Call me snarky but instead of just multiply/devide by 1.6, you rather prefer remembering the Fibonacci numbers up to, I don't know, 200 to be useful?
by yegle 2y ago
Call me snarky but instead of just multiply/devide by 1.6, you rather prefer remembering the Fibonacci numbers up to, I don't know, 200 to be useful?
- nrr 2y agoIn practice, at least in my experience, only up to 13. (Though, I have the sequence memorized up to 21 because of a sign outside Chattanooga[0], which is what gave me my "hey, wait" moment about this.) A combination of both the fundamental theorem of algebra and Zeckendorf's theorem has allowed me to fill in the rest so far. For example, 25 mi = 5 * 5 mi, which yields 5 * 8 km = 40 km. As it turns out, that is how far Cleveland, TN, lies from Chattanooga. 0: https://usma.org/metric-signs/tennessee https://usma.org/metric-signs/tennessee
- sigmoid10 2y ago>A combination of both the fundamental theorem of algebra and Zeckendorf's theorem How do you apply the fundamental theorem of algebra here?
- bobbylarrybobby 2y agoI will go out on a limb and assume they meant the fundamental theorem of arithmetic, that all numbers can be (uniquely) factored into primes.
- battles 2y agoThat's what I was thinking. I good example of over-engineering though.
- dylan604 2y agoSome people think differently. Some methods click with some people, while making others think it's making it overly complicated. The new math drove people crazy. The concept of doing extra math by rounding a number up to a whole number, and then subtracting the diff seems like a lot of work, but is amazing when used frequently to do "in your head" type of work. That extra match can lead to an answer faster than traditional math
- jmholla 2y agoYea, and since it's the golden ratio, the division is roughly the same as multiply by 60%. So you can just remember to take 60% and add it to the original or treat it as the answer depending on if you're going to or from the smaller measurement.
- btilly 2y agoThe list isn't that long. 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, and 144. I memorized this almost by accident. I was doing hand rolled spaced repetition system for conditioning myself to fix some bad habits, and they came up often enough that it was memorized.
- jameshart 2y agoJust spend a few sprints in a sufficiently dysfunctional agile team and you’ll learn all sorts of higher Fibonacci numbers.
- Terr_ 2y agoTechnically they could also also be functional teams with a long history of gradual point drift... Though most organizations shake teams up before then.
- btilly 2y agoIf a ding that gets mentioned in planning is 1 point and they regularly try to fit 144 point projects in a sprint without splitting it up, that's likely to be rather dysfunctional. I mean it is possible that gradual point drift would get there. But sufficiently improbable that I know what I'm betting on.
- shultays 2y agoFor some reason we are using 20 instead of 21. I didn't even bother asking why
- rahkiin 2y agoThat is because fibonacci is used to indicate the ‘guess’timation part. 5 Instead of ‘twice as much work as a 2’ (4). The idea is when you get higher numbers the opposite happens: 21 sounds like a very specific number and not like a rough guess. 20 does. So it becomes 1 2 3 5 8 13 20 40 inf ?
- jraph 2y agoIt's art. It's possibly not very useful (who knows, though?), but some will find beauty, joy, entertainment, surprise, amazement, incredulity, anger, disdain, indignation, fear, nostalgia in this. Others will feel the deepest and purest indifference.
- JustSomeNobody 2y agoHow often you drive 200mph??
- yegle 2y agoI think it's more common to convert distances. I consider any distance reachable with one tank of gas commonly used (so up to 400 miles).
- amarcheschi 2y agoI'm even lazier, 1.6 might be hard to do without a Calc, I just grab 50% of the original number, 10%, and then sum them to the original
- throwadobe 2y agoThat's how I do many kinds of percentages... like 72% is 50% and then 10% twice and then a couple of 1%s
- huhtenberg 2y agoIn the same vein, converting pounds to kilos is "divide by 2, subtract 10%".
- amarcheschi 2y agono way just discovered this lmao i now only need a similar thing for fahrenheit to c/viceversa, i'm sure it exists. however, i'm so lazy i will not search for that information now
- venusenvy47 2y agoFor Celsius to Fahrenheit, just double it and add 30. It gets you pretty close for the temperature range that humans live in.
- comradesmith 2y agoHere’s a practical solution based on this: Take your kilometres e.g 60, divide by 5 -> 12, now times that by 3 -> 36. Take your miles e.g 80, divide by 5 -> 16, times 8 -> 80 + 48 -> 128 So any conversion reasonable conversion can be done in your head with your 3, 5, and 8 times tables
- deleted 2y ago[deleted]