Math problem - what's your answer?
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Anonymous
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It took Mr. Sawyer 20 minutes to cut a log into 5 pieces. How many minutes would it take him to cut a log into 10 pieces?
This was a continental math league problem (4th grade). Clearly the correct answer isn't the obvious one  Just curious if others think the way they're looking for you think...
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Anonymous
| 45 minutes |
Anonymous
| Is this supposed to be a riddle? |
Anonymous
| Can Mr. Sawyer cut said 5 pieces in half and get his 10 pieces that way? |
Anonymous
This would be my answer, as well. |
Anonymous
| 25? |
Anonymous
| Yes. 4 cuts to get 5 pieces, so 5 minutes per cut. 9 cuts to get 10 pieces, so 9x5=45. |
Anonymous
+1. 5 mins/cut, 9 cuts to make 10 pieces. |
Anonymous
| 20 minutes |
Anonymous
| 24 . Four minutes per chop and he can just chop across all the five pieces once to get 10 |
Anonymous
| Is it the same log or a different log? |
Anonymous
| 9 cuts. Each takes 5 mins. 45 mins. |
Anonymous
| Cut in 1/2 the 5 pieces Equals 10. |
Anonymous
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so, he had to make 4 cuts to get it into 5 pieces, so assuming the log is even and not tapered, each cut took 5 min.
So he needs to make 9 cuts to make 10 pieces, so that would be 9x5=45 min. Right? |
Anonymous
| You basically just have to go through it in your mind and figure out you always need one fewer cut than pieces. |