A red metal sheet has the shape of a two-foot square with semicircles on opposite sides. If a disk with a diameter of two feet is removed from the center, what is the area of the remaining metal?
 M. Gardner, The Colossal Book of Short Puzzles and Problems, (D. Richards, ed.), New York: W. W. Norton & Company, 2006 p. 109.
Wolfram Demonstrations Project
Published: May 23 2014