# Sunday Afternoon Maths XIV

**Posted on 2014-05-25**

## 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!)

## Eight peas

Source: Source: Maths Jam

There are eight cups, with one pea in each cup. You are allowed to move a pea by picking up the pea in a pot with only one pea and jumping it to the left or the right over two peas into a pot with only one pea in it. For example, the following moves are allowed:

Starting with your eight cups, can you make four moves?

If you enjoyed these puzzles, check out Advent calendar 2019,

puzzles about star numbers, or a random puzzle.

puzzles about star numbers, or a random puzzle.