math

I read a book called Math For Smarty Pants. It has lots of great puzzles.

The Number Four (There's a clue about it.)
Pick any number. For example, 72.

Write that number. 72

Now, write it in words. seventy-two.

Now count the letters in that word. 10

Write that number in words. ten.

Now count the letters. 3

Now write that word. three.

How many letters in that word? 5.

Write that word. five.

Now count the letters in that word. 4.

Now keep doing it. Your always going to get four.