Episode 544: The M&M Anomaly

David Kestenbaum noticed that a pack of Milk Chocolate M&M's weighs 1.69 ounces, but a pack of Peanut Butter M&M's weighs 1.63 ounces. He had to know why. But the confectionery world has its secrets.

(Image credit: Quoctrung Bui/NPR)