MIND GAMES

In Reader's Digest 

 

Lateral Thinking Puzzles

Sterling Publcations

Paul Sloane 

A London cabdriver picked up a woman who was a notorious chatterbox. He didn't want to engage in conversation, so he pretended to be deaf. He pointed to his mouth and ears to indicate that he could neither speak nor hear. As she was about to get out of the taxi, he pointed to the meter so she could see how much money she owed. She paid him and walked off. Then she realized he could not have been a deaf-mute. How did she know?

Answer:

 

The cabbie must have heard her initial instructions, or he would not have known where to take her.