A farmer has a rectangular field twice as long as it is wide. He constructs a straight fence across the field, parallel to the shorter sides, dividing it into two smaller enclosures. One enclosure is a square with an area of 400 square meters. What is the total area of the original field?
800 square meters
The square enclosure has an area of 400, meaning its side length is 20 meters. Since it was cut parallel to the shorter side, the field's width is 20 meters. The length of the field is twice the width, so 2 * 20 = 40 meters. Total area = 20 * 40 = 800.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Medium. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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