A rectangle has an area of 48 square centimeters. Its length is 3 times its width. What is the perimeter of the rectangle in centimeters?
32 cm
Let width be w. Length is 3w. Area = w * 3w = 3w^2 = 48, so w^2 = 16, meaning w = 4 and length = 12. Perimeter = 2(4 + 12) = 32 cm.
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: Medium. More like this: Math riddles with answers or try Target 24 for a different kind of puzzle.
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