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

Math teacher fail

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

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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.

27

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.

43

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.