The recent article by Marilyn v.S. said that if you bought 2 tickets in a lottery that had a 1-in-80million chance of winning…you would have a 2-in-80million chance of winning.

That doesn’t seem right, although it’s probably a good approximation. What’s the more precise answer? Better yet, what’s the equation used to calculate the answer?

An easier example would be flipping a coin where you “win” if you get tails. You have a 1-in-2 chance of winning. But if you flip twice, you do not have a 2-in-2 chance (100%) because we all know that it’s totally feasible to get heads twice in a row.