I love this story about a retired couple exploiting a rule in a state-run lottery game to make millions of dollars.

Jerry Selbee: Here’s what I said. I said if I played $1,100 mathematically I’d have one 4-number winner, that’s 1,000 bucks.  I divided 1,100 by six instead of 57 because I did a mental quick dirty and I come up with 18. So I knew I’d have either 18 or 19 3-number winners and that’s 50 bucks each. At 18 I got $1,000 for a 4-number winner, and I got 18 3-number winners worth $50 each, so that’s 900 bucks. So I got $1,100 invested and I’ve got a $1,900 return.

Via 60 Minutes