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Matching Socks

Pro Problems > Math > Statisics and Probabilities > Probability
 

Matching Socks

I am holding a blue sock and a green sock. In my drawer I have 4 red socks, 2 green socks, and some blue socks. If I pick one sock at random from the drawer, the probability that I’ll be holding a match is
2
3
. How many blue socks are in the drawer?
 

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Problem by Mr. Twitchell

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