sactoking
Diamond Member
- Sep 24, 2007
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Actually, both 15 and 20 would be correct.
Let's assume that the board is of some arbitrary size, like 10"x10". The cutter is using a handsaw that can cut at the rate of 1"/min.
The cutter cuts through the middle of the board, you have 2 pieces that are 5"x10", and it takes 10 minutes.
If the cutter wants three pieces there are two options:
1) The cutter cuts off one third of the board. It is a 10" cut that takes 10 minutes and the cutter now has a 3.3"x10" piece and a 6.7"x10" piece. The cutter then cuts the larger piece in half the long way, which is a 10" cut and takes 10 minutes. The cutter now has three boards that are 3.3"x10" and it took 20 minutes to get them.
2) The cutter cuts the board in half. It is a 10" cut that takes 10 minutes and the cutter now has two pieces that are 5"x10". The cutter then cuts one piece in half the short way, which is a 5" cut and takes 5 minutes. The cutter now has one board that is 5"x10" and two boards that are 5"x5" and it took 15 minutes to get them.
So, really, both answers are theoretically right. The problem is, as usual, that pattern recognition problems often lack sufficient information to isolate one, and only one, plausible pattern.
Let's assume that the board is of some arbitrary size, like 10"x10". The cutter is using a handsaw that can cut at the rate of 1"/min.
The cutter cuts through the middle of the board, you have 2 pieces that are 5"x10", and it takes 10 minutes.
If the cutter wants three pieces there are two options:
1) The cutter cuts off one third of the board. It is a 10" cut that takes 10 minutes and the cutter now has a 3.3"x10" piece and a 6.7"x10" piece. The cutter then cuts the larger piece in half the long way, which is a 10" cut and takes 10 minutes. The cutter now has three boards that are 3.3"x10" and it took 20 minutes to get them.
2) The cutter cuts the board in half. It is a 10" cut that takes 10 minutes and the cutter now has two pieces that are 5"x10". The cutter then cuts one piece in half the short way, which is a 5" cut and takes 5 minutes. The cutter now has one board that is 5"x10" and two boards that are 5"x5" and it took 15 minutes to get them.
So, really, both answers are theoretically right. The problem is, as usual, that pattern recognition problems often lack sufficient information to isolate one, and only one, plausible pattern.