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'Unsolvable' exam question leaves Chinese students flummoxed

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Re: 'Unsolvable' exam question leaves Chinese students flummoxed

#41

Post by JoeAltmaier »

jasikpark wrote: post #20
RubenSandwich wrote: post #4

It sounds like the old programming interview questions: "Why are sewer covers round?", etc. They sound like they promote critical thinking, but really they just confuse the applicants. If you want to know how someone thinks, ask them to solve a problem step by step.

i only know from learning about it, but round manhole covers prevent them from falling through the hole by consisting of a curve of constant width. Another example is the Reuleaux Triangle which is a viable shape for manhole covers. https://en.m.wikipedia.org/wiki/Reuleaux_triangle

Cool! I didn't know this was a thing, but I came up with the same solution independently when asked this question.

It also makes a wheel that has a constant tangent from the ground (not a constant axel point) as it turns.

Re: 'Unsolvable' exam question leaves Chinese students flummoxed

#42

Post by js8 »

mannykannot wrote: post #29
ensignavenger wrote: post #5

Growing up in the US, we used to have questions like this on math exams. The correct answer is something to the effect of "Not enough information to solve this problem". Of course we had practice questions where that was the case before the exam, so it wasn't a surprise or anything... but it was standard practice.

Then there are the questions that, at first sight, do not seem to have all the information, yet they do. Consider the one that opens this article: http://www.solipsys.co.uk/new/NapkinRingVersusSphericalCap.h...

> Then there are the questions that, at first sight, do not seem to have all the information, yet they do.

I love the following problem, in a similar vein:

There are two chosen natural numbers x and y, both between 1 and 100. Two smart people, Alice and Bob, are told this fact, and Alice is secretly told x*y, and Bob is secretly told x+y, and they are also told who knows what. Then the following conversation happens:

Alice: I don't know the two numbers.

Bob: I knew you wouldn't know them.

Alice: Now I do know the two numbers.

Bob: And now I do know them as well.

The question is, what are the two numbers?

Re: 'Unsolvable' exam question leaves Chinese students flummoxed

#43

Post by floren »

It's a classic nonsense word problem, first appearing in 1841: https://en.wikipedia.org/wiki/Age_of_the_captain

It's also been used to examine how students react to nonsensical word problems, and this is to some extent backed up by the school's statement. However, given the reputation of Chinese schools, it's entirely possible the teacher preparing the test simply threw it in because it looked like a word problem and the school is just saving face.

Re: 'Unsolvable' exam question leaves Chinese students flummoxed

#44

Post by js8 »

tzs wrote: post #38
RubenSandwich wrote: post #4

It sounds like the old programming interview questions: "Why are sewer covers round?", etc. They sound like they promote critical thinking, but really they just confuse the applicants. If you want to know how someone thinks, ask them to solve a problem step by step.

> "Why are sewer covers round?" Because sewer access holes are round.

Because the manufacturer was cutting corners. ;-)

Re: 'Unsolvable' exam question leaves Chinese students flummoxed

#45

Post by JackFr »

floren wrote: post #43

It's a classic nonsense word problem, first appearing in 1841: https://en.wikipedia.org/wiki/Age_of_the_captain It's also been used to examine how students react to nonsensical word problems, and this is to some extent backed up by the school's statement. However, given the reputation of Chinese schools, it's entirely possible the teacher preparing the test simply threw it in because it looked like a word problem and…

> However, given the reputation of Chinese schools, it's entirely possible the teacher preparing the test simply threw it in because it looked like a word problem

Action: Chinese school tries to break stereotype.

Result: stereotype reinforced, because people would rather believe that than the explicit explanation.

Re: 'Unsolvable' exam question leaves Chinese students flummoxed

#46

Post by watwut »

RubenSandwich wrote: post #4

It sounds like the old programming interview questions: "Why are sewer covers round?", etc. They sound like they promote critical thinking, but really they just confuse the applicants. If you want to know how someone thinks, ask them to solve a problem step by step.

The are squared sewers holes all around the world. At least, in front of my house, next to workplace and I encountered multiple others on my way between work and home today.

Re: 'Unsolvable' exam question leaves Chinese students flummoxed

#47

Post by mcphage »

JoeAltmaier wrote: post #35
Harvey-Specter wrote: post #33

Earlier quoted context omitted.

No, there isn't. Please quote what other information is provided.

The other information, is the reasonable assumption that there is a minimum age limit for getting a license, and an apprenticeship for larger vessels. As mentioned. Even if you don't know the numbers, you can sketch out that thought process for an answer. Not all algebra is done with constants. In fact my sister ran the data systems for a large trucking company. Her interview questions included "how many ping pong ba…

There still isn't an answer to the problem.

Re: 'Unsolvable' exam question leaves Chinese students flummoxed

#48

Post by t0mbstone »

js8 wrote: post #42
mannykannot wrote: post #29

Earlier quoted context omitted.

Then there are the questions that, at first sight, do not seem to have all the information, yet they do. Consider the one that opens this article: http://www.solipsys.co.uk/new/NapkinRingVersusSphericalCap.h...

> Then there are the questions that, at first sight, do not seem to have all the information, yet they do. I love the following problem, in a similar vein: There are two chosen natural numbers x and y, both between 1 and 100. Two smart people, Alice and Bob, are told this fact, and Alice is secretly told x*y, and Bob is secretly told x+y, and they are also told who knows what. Then the following conversation happens:…

4 and 13

Re: 'Unsolvable' exam question leaves Chinese students flummoxed

#49

Post by lalaland1125 »

js8 wrote: post #42
mannykannot wrote: post #29

Earlier quoted context omitted.

Then there are the questions that, at first sight, do not seem to have all the information, yet they do. Consider the one that opens this article: http://www.solipsys.co.uk/new/NapkinRingVersusSphericalCap.h...

> Then there are the questions that, at first sight, do not seem to have all the information, yet they do. I love the following problem, in a similar vein: There are two chosen natural numbers x and y, both between 1 and 100. Two smart people, Alice and Bob, are told this fact, and Alice is secretly told x*y, and Bob is secretly told x+y, and they are also told who knows what. Then the following conversation happens:…

Before anyone else gets lost trying to solve this, the parent posted the puzzle incorrectly.

The correct limits on the numbers are that: - Each of them is greater than 1, but their sum is less than 100

Re: 'Unsolvable' exam question leaves Chinese students flummoxed

#50

Post by JoeAltmaier »

mcphage wrote: post #47
JoeAltmaier wrote: post #35

Earlier quoted context omitted.

The other information, is the reasonable assumption that there is a minimum age limit for getting a license, and an apprenticeship for larger vessels. As mentioned. Even if you don't know the numbers, you can sketch out that thought process for an answer. Not all algebra is done with constants. In fact my sister ran the data systems for a large trucking company. Her interview questions included "how many ping pong ba…

There still isn't an answer to the problem.

Sure - in the form of bounds (older than...younger than).

This is all about students being taught by rote, with right answers all neat and pat and solvable. Folks educated like that have a problem with questions like this one. Folks who can 'think outside the box' have no issue at all with uncertainty in the answer.

Similarly, folks posting here who can or cannot see that this question is interesting and solvable (do a degree). No, not by 'an answer' but by a variety of approaches.

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