The Messy Girl
Probability puzzles require you to weigh all the possibilities and pick the most likely outcome.
A messy girl had 24 socks in the drawer at her bedroom. There are 6 pairs of red socks, 5 pairs of green socks, and 1 pair of blue ones, but all the socks are mixed up. One night she wanted to go out and went to her bedroom for a pair of socks. As she turned on the light, the lamp didn't work, so she had to find her socks in complete darkness.
What's the smallest number of socks she had to take downstairs to be sure to have a matching pair?
Answer
She only had to take 4 socks downstairs. If the first 3 she took were all of a different color, the 4th must match with one of the others.
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Comments
spstinger
Feb 15, 2002
 This answer is incorrect, she could have 4 white socks, she needs at least seven 
brain_crusher
Feb 15, 2002
 It was confusing at first, I got lost in the information... 
Captbob61
Mar 20, 2002
 sp stinger....
What? 
think_about_it13
Apr 02, 2002
 if you have four white socks u would have a pair... duh... 
chamber44
May 17, 2002
 spstinger is wrong. Good puzzle. 
im_para_noid
Jun 08, 2002
 I think she could take two. If she grabbed the same pair of socks, she would have a pair 
andy1608
Jun 21, 2002
 This whole problem is just a reminder to keep your socks bound in pairs, in case of a blackout. 
george1978
Aug 01, 2002
 But in the Question there is never any mention of white socks 
cheshirecatgirl
Oct 13, 2002
 hello! you didnt mention that the socks weren't paired up because, then if like you stated them as a pair. making her to only have to chose 1 pair. 
electronjohn
Dec 03, 2002
 I_am_para_noid is wrong. If she took only two socks she might have a matching pair but she would not be "sure" of having a matching pair which is what the question states. Great question. I was going to post it if it was not already here. 
PhilDunphy
Mar 20, 2003
 Good teaser, almost caught me out 
bluetwo
May 07, 2004
 eh, forget about colors... i go by thickness... 
Anupriya9
Oct 03, 2004
 Great teaser! If they were toesocks, you would have a different answer though 
mr_brainiac
Jan 29, 2006
 If she's messy, she's probably pretty lazy too. She most likey wouldn't want to have to pull out any more socks than she had to (such hard work) or even care if they were mismatched. If she took out only 2 socks, she'd still have better than a 40% chance of having a match, which would probably be acceptable odds for such a slug. If she can fit both feet into one sock and hop around like a pogo stick, she could get by with only 1 sock, which is certainly bound to be a match. (Pardon the wise cracks, I'm just being a doofus.)
Good old standard puzzle though, I enjoyed it. 
YVAU
Mar 07, 2006
 Nice and easy, the way I like them. I go by smell personally. Or I just wear very long pants hence removing the need for matching socks. Boots work well too. 
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