A carpenter has several boards of equal length. He cuts 3/5 of each board. After cutting the boards, the Carpender notices that he has enough pieces left over to make up the same length as four of the original boards. How many boards did the Carpender start with?

Answer 1

there are b boards
after cutting, there are lengths totalling b * 2/5 left over

so, after cutting 5 boards, he has enough leftovers to make 2 original lengths.

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