Oddly Divided

In the arrangement the glasses were shown in, dividing the pennies among the glasses so each glass held an odd number of pennies is impossible. This can be demonstrated with the simple logic that any three odd numbers added together yield an odd number.

The trick, as you probably guessed, was to change the arrangement of the glasses so a penny could be in more than one glass. By placing an even number of pennies into a glass, an odd number of pennies into a second glass, and then placing the second glass into the first, both glasses contain an odd number of pennies. One example, shown to the right, has two pennies in one glass, three pennies inside a glass within the first glass, and five pennies in the third glass.