I release a fish at the edge of a circular pool. It swims 80 feet in a straight line and bumps into the wall. It turns 90 degrees, swims another 60 feet, and hits the wall again. How wide is the pool?
It sounds as if there’s not enough information to solve this, but there is if you remember that when a right triangle is inscribed in a circle, its hypotenuse is the diameter. The pool is 100 feet wide.
August 4, 2012 | Puzzles
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