A farmer has a rectangular field measuring 40 meters by 30 meters. He wants to build a straight fence that divides the field into two parts of equal area. What is the minimum possible length of this fence?
30 meters
To divide a rectangle of 40x30 into two equal areas with the minimum fence length, you draw a line parallel to the shorter side (30 meters) right through the center. The length of this fence is equal to the width of the field, which is 30 meters.
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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