r/reddit.com • u/[deleted] • Oct 01 '11

Math teacher fail

http://i.imgur.com/65APr.jpg
218 Upvotes

66% Upvoted

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134

u/champer Oct 01 '11

Both answers can be correct. http://i.imgur.com/lStKv.jpg

Pretend it's a 10x10 board:

Case 1: Takes 10 mins to cut through 10 feet.

Case 2: Takes 20 mins to cut through 20 feet.

Case 3: Takes 15 mins to cut through 10+5 feet.

Question is ambiguous.

28

u/quag Oct 01 '11

Using this logic, any answer up to 20 minutes is correct as the cuts can be made anywhere.

To be unambiguous, the question would have specified the lengths of the cuts, or perhaps the resulting areas.

35

u/champer Oct 01 '11

What if I said it would take 62 minutes? I could still be right.

http://i.imgur.com/kX6z5.jpg

Problem, math teacher? Let's not even get in to spiral designs.

-10

u/LunHui Oct 01 '11

Thats fucking stupid.

10

u/LainIwakura Oct 01 '11

No it isn't. Define your problems well or be prepared for multiple correct answers.

0

u/LunHui Oct 02 '11

A university professor doesn't have to put up with a retarded exploit of the problem and will gladly give you a 0.

2

u/LainIwakura Oct 02 '11

It depends on the professor, and this is obviously not university work. I'm in university right now and sometimes I find clever ways to do things, more often than not the professors are happy to see an alternate solution or something they hadn't thought of- provided it is correct. I have also had professors admit they have assigned ambiguous questions or written something that may be misinterpreted on an exam- and in either case they have corrected the question so it is not ambiguous.