Blindly Picking Socks

You have 12 black socks and 12 white socks mixed up in a drawer. You’re up very early and it’s too dark to tell them apart. What’s the smallest number of socks you need to take out (blindly) to be sure of having a matching pair?

Sock drawer

Three socks. If the first sock is black, the second one could be black, in which case you have a matching pair. If the second sock is white, the third sock will be either black and match the first sock, or white and match the second sock.

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8 Comments on "Blindly Picking Socks"


Ivy says
August 13, 2014 @ 09:19

Only three. You will either get three of the same color, two black and one white or vice versa.


Maria says
February 19, 2015 @ 09:35

To be 100% sure and to be able to bet ur life on it u need to take out 13 socks!


Maria says
February 19, 2015 @ 09:36

Sorry, misread! I thought it asked for a black pair, not a matching pair. Yeah, it is 3 then!


GraceyCakes says
November 22, 2016 @ 18:47

13, because if you take out 3 black socks… OH NVM IM STOOPID XD


Walter says
January 16, 2019 @ 22:22

you have to pick 25 socks because there are 24 of each color.


Dan says
January 17, 2019 @ 10:13

There are only 24 socks in the drawer.


Smith says
January 5, 2021 @ 15:02

Still don’t understand


Derick says
February 4, 2021 @ 21:50

3, because the only possible ways you can pick a pair out of 3 socks are:

black black black
black black white
black white white
white white white

And you’ll notice that all of these triplets have at least two of them matching
two wouldn’t work because you could get a

black white
black black
white white

which isn’t guarenteed


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