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Age 11 to 14
Challenge Level

I start with 3 marbles, one red, one green and one blue.
I can trade any one marble for two others, one each of the other two colours.

Is it possible to make a number of such trades and end up with five more blue marbles than red?
I don't care how many green marbles I have at the end.

After this problem you may like to take a look at More Marbles