basic question but need good explanation please

[SplawnDarts]

This kind of [censored] cannot be "explained" to someone who doesn't want to learn. You're wasting your time.

Your best bet for teaching him if you really want to is to bust his bad-at-math ass flipping coins. Start flipping a coin, and every time it comes up the same way twice (or three times or whatever), let him bet 11 to 10 that it won't do it again - that's more than enough vig to cover the bias in any standard US coin.

When he's broke, he might be more receptive to basic probability theory.