A rectangle has a perimeter of 36 inches. Its length is twice its width. What is the area of the rectangle in square inches?
72
Perimeter = 2(length + width) = 36, so length + width = 18. Since length = 2 width, 3 width = 18, so width = 6 and length = 12. Area = 6 * 12 = 72.
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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