If a brick balances evenly with three-quarters of a brick and a three-quarter pound weight, how much does the full brick weigh in pounds?
3 pounds
Let b be the weight of the brick. b = 0.75b + 0.75. Subtracting 0.75b from both sides gives 0.25b = 0.75. Multiplying by 4 gives b = 3.
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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