The Penny Square Puzzle
This activity is adapted from a puzzle in a book by Boris Kordemsky, The Moscow Puzzles: 359 Mathematical Recreations. Like many mathematical puzzles, The Penny Square Puzzle will take persistence and creativity to solve. In the puzzle, students are shown 12 pennies arranged to form a square with four pennies on each side. They are then challenged to use 12 pennies to form a square with fi ve pennies on each side. While at first the puzzle seems impossible, creative thinking, logic, and working with 12 pennies should lead to a solution.
Get Puzzle (280k PDF file; Require Adobe Reader)