Suppose you have 11 black socks and 11 green socks in the dryer.
4. Without looking, how many socks would you need to pull out of the dryer to be sure you get a black pair?
Answer: 13. Why? because of the extremely unlikely case that the first 11 you
pull out would all be green, then in that case your 12th and 13th socks
would have to be black because there would be no more green ones left to
pull out, but very likely you wouldn't need to pull out nearly that
many.
5. Without looking, how many socks would you need to pull out of the dryer to be sure you get a matching pair (of any color)?
Answer: 3. Why? Because there are only two colors and three socks can't all be
different colors.
Edwin