Matching Socks Puzzle - Solution

The Puzzle:

Matching Socks
You are about to leave for holiday, but you forgot socks!

You race back to your room, but the power is off so you can't see sock colors.

Never mind, because you remember that in your drawer there are ten pairs of green socks, ten pairs of black socks, and eleven pairs of blue socks, but they are all mixed up.

How many of your socks do you need to take before you can be sure to have at least one matching pair?

Our Solution:

The answer is four.

Although there are many socks in the drawer, there are only three colors, so if you take four socks then you are guaranteed to have at least one matching pair.
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