An eccentric mathematician has 10 identical white socks and 10 identical black socks in his drawer. If he selects his socks at random in a dark room, how many socks must he extract to ensure he has a matched pair?
Answer: He must select 3 socks to ensure he has a pair of the same color. Many people answer “11 socks,” but that is the number needed to ensure he has a pair of a specific colour.
