5 ms·

I get interested in the response to these sorts of problems. Both in the comments here and over at Tao's post, there are a lot of examples of brute force soluti

I get interested in the response to these sorts of problems. Both in the comments here and over at Tao's post, there are a lot of examples of brute force solutions. This seems like a common response to recreational mathematical problems, and it has always seemed to me like it's missing the point. These questions aren't generally posed because people care about the answer, but because there are interesting or surprising ideas involved in working it out. In this problem, I guess the surprising thing would be that you are actually given sufficient information to find the answer. The simplest brute force approaches can tell you this, but don't tell you anything about why that may be. I'm reminded of Hamming's motto: "the purpose of computing is insight, not numbers."

msandford 12y ago
I would have thought that the point of the post is "how effing ridiculous is it that we're giving kids severely broken problems?!" I'm all for giving kids more open-ended problems so that they get a chance to think and explore, but this one is ridiculous. They each sell one chicken for $35 in the morning and give the rest away in the afternoon is a valid solution and yet utterly, utterly wrong since the odds of something like that happening in real life are basically nil. If you're going to give kids an under-constrained problem like this at least make the solution a line rather than a surface so that way you're only screwing with their heads some instead of a lot.
- bkcooper 12y ago
  Given the description, it sounds like this problem was given to a club of kids who do recreational/contest problems, which makes a pretty big difference. I think they probably get the spirit in which it is offered and understand the implicit constraints (e.g. no giving away chickens).
- deleted 12y ago
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- sanderjd 12y ago
  This is clearly not intended to screw with their heads. It is likely the problem-poser didn't realize the issue with not constraining the afternoon price to be greater than zero. In fact, figuring out that little quirk is already a good intellectual exercise for the student, and it's easy for the teacher to say "great answer! what if you can't set the afternoon price to zero?". Honestly, I think this kind of attitude about problems is what is "effing ridiculous". There is huge value in learning to question the constraints of a problem.
- bluecalm 12y ago
  It's pretty clear from problem description that they are not giving away the chickens in the afternoon. They lowered the price and came back selling. It's just doesn't happen in the real life that people call giving away selling. Also in natural language you would expect significantly different wording if they all made 35$ before lunch and then decide to just give remaining chickens for free. Another thing is usage of the word sell. You would have hard time selling anyone an idea that sell could mean give away in the context. Understanding how natural language works and being able to write reasonable constraints based on this description is an important skill. Assuming the price could be 0 in the afternoon is just an error on solvers side.

msandford 12y ago

I would have thought that the point of the post is "how effing ridiculous is it that we're giving kids severely broken problems?!" I'm all for giving kids more open-ended problems so that they get a chance to think and explore, but this one is ridiculous. They each sell one chicken for $35 in the morning and give the rest away in the afternoon is a valid solution and yet utterly, utterly wrong since the odds of something like that happening in real life are basically nil. If you're going to give kids an under-constrained problem like this at least make the solution a line rather than a surface so that way you're only screwing with their heads some instead of a lot.

bkcooper 12y ago
Given the description, it sounds like this problem was given to a club of kids who do recreational/contest problems, which makes a pretty big difference. I think they probably get the spirit in which it is offered and understand the implicit constraints (e.g. no giving away chickens).
deleted 12y ago
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sanderjd 12y ago
This is clearly not intended to screw with their heads. It is likely the problem-poser didn't realize the issue with not constraining the afternoon price to be greater than zero. In fact, figuring out that little quirk is already a good intellectual exercise for the student, and it's easy for the teacher to say "great answer! what if you can't set the afternoon price to zero?". Honestly, I think this kind of attitude about problems is what is "effing ridiculous". There is huge value in learning to question the constraints of a problem.
bluecalm 12y ago
It's pretty clear from problem description that they are not giving away the chickens in the afternoon. They lowered the price and came back selling. It's just doesn't happen in the real life that people call giving away selling. Also in natural language you would expect significantly different wording if they all made 35$ before lunch and then decide to just give remaining chickens for free. Another thing is usage of the word sell. You would have hard time selling anyone an idea that sell could mean give away in the context. Understanding how natural language works and being able to write reasonable constraints based on this description is an important skill. Assuming the price could be 0 in the afternoon is just an error on solvers side.