NPR's Ayesha Rascoe plays the puzzle with listener Jean Kendrick and puzzlemaster Will Shortz.

This brain-teasing math problem created by Puzzles9 presents three pentagons, each with a set of five numbers. But there's a catch — the middle pentagon is missing a number in the bottom right ...

The number in each polygon with n sides is the sum of the first n prime numbers’ values. The following applies to the decagon: We’d love to hear from you! E-mail us at [email protected] to share ...