Click here to win prizes by solving the puzzle Advent calendar.
Click here to win prizes by solving the puzzle Advent calendar.


Sunday Afternoon Maths XIV

 Posted on 2014-05-25 


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!)

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Tags: speed

Eight peas

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?

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