posted by monica on .
Your sock drawer has 10 blue socks, 16 red socks, and 12 white socks. If you reach into the drawer in the dark, how many socks do you need to pull out to be sure you have a matching pair?
I can't figure out.
Since there are only 3 colors of socks, the fourth pick is sure to give you a matching pair.
There are 3 different colors, so regardless of how many there are of each one, even if worst case scenario, you take out a blue sock first, then a red one and then a white one, the next color has to be one of them, so you would have a pair, so the answer is 4
But what if you pull out four of one color socks?