How can you take 9 toothpicks and make ten without breaking the toothpicks?
TEN (every line making the letters in the word ten is one toothpick. There are nine lines you draw when writing ten, so there are 9 toothpicks making TEN).
In a drawer you have black socks and white socks. They are not stored away in pairs. Without looking, how many times will you have to reach into the drawer to come out with a matching pair?