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 Pairs of Socks (Posted on 2004-09-01)
You are in a pitch black room and need to get a pair of socks out of your drawer which can contain up to 100 socks. In the drawer is a mixture of black and white socks, and there's at least one pair of either color. If you choose two socks, the chance that you draw out a black pair is 2/3.

What is the chance that you draw out a white pair?
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Bonus: what would the answer be if the drawer contained between 100 and 1000 socks?

 See The Solution Submitted by SilverKnight Rating: 3.0000 (1 votes)

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 Solution to 1st part | Comment 6 of 20 |
Initially there are 55 socks in the drawer, 45 of these are black.

this gives the equation as

(45/55)*(44/54)=0.66666667, for a black pair,

switching this for the white gives

(10/55)*(9/54)=0.030303.

 Posted by Juggler on 2004-09-01 18:28:13

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