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Pairs of Socks (Posted on 2004-09-01) Difficulty: 3 of 5
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?
______________________________________________

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)

Comments: ( Back to comment list | You must be logged in to post comments.)
Solution 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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