This is Why I'm an English Teacher

There are three vending machines and all of them are mislabeled. One machine dispenses only Coke, the other machine dispenses only Pepsi, and the final machine randomly dispenses Coke or Pepsi. Each pop is a dollar.

How many loonies will it take to determine which vending machine as only Coke, only Pepsi, and Coke and Pepsi?

Our lovely Psychology professor posed this question to the class today, and I have to say the answer shocked me. It was so logical and so surprising that I had to exclaim, "This is why I'm an English teacher."

Have fun, good luck

Until Next Time, 

LC