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'Two and One' printed from http://nrich.maths.org/

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Two children are playing a game with three balls, two blue ones and one red one.
Terry is red and Ali is blue.

two blue balls and a red ball

They toss up the balls, which run down a slope so that they land in a row of three, like this:

blue, red, blue balls in a line

The colour in the middle wins that round. Is this a fair game?
Who do you think will win?
Why?

Try using the interactivity below to get a feel for the game. (The sum column tells you how many times Terry has won so far.)

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