Clue to Puzzle #52: Different Coloured Socks in a Draw.

52. 100 black and white socks are in a drawer. How many socks must you pull out before you are guaranteed to have a pair? Generalize to socks of N different colors.
picture of a striped sock


To be clear we are assuming socks are either black or white, and a pair constitutes either two black or two white socks.

The Puzzle

So we need to think about the worst case scenarios after drawing a certain number of socks. If we have taken two socks we could have a pair, or we could have one of each. What about if we pull another sock, and another one.

Extend this to N different colours.

Where next?
Questions Answer

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