# Puzzles

## Superdog

Source: Futility Closet

A dog is running along a beach at 2m/s. The dog's owner blow a whistle every 10 seconds. Each time the dog hears a whistle, she doubles her speed. How many whistles will the dog hear?

(Hint: speed of sound = 343m/s)

(Hint 2: The answer is not eight!)

If you enjoyed this puzzle, check out Sunday Afternoon Maths XIV,

puzzles about speed, or a random puzzle.

puzzles about speed, or a random puzzle.