A merchant has a 40-pound block of weight and a scale. What is the minimum number of pieces he can break the block into to be able to weigh any whole pound amount from 1 to 40 using a balance scale?
4 pieces
Using powers of 3, the weights needed are 1, 3, 9, and 27 pounds. These four pieces can weigh any integer amount from 1 to 40 pounds.
About this riddle
Math riddles hide a calculation inside a short story. Pull out the numbers, work out what is being asked, and watch for a trick such as a unit change.
Difficulty: Hard. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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