Let me write this down. And this insight actually came from one of the middle school students in the summer camp that Khan Academy was running. It's actually a fabulous way to think about this. So if you pick wrong, so if it's step 1, so initial pick is wrong. So you pick one of the two wrong doors, and then in step 2, you always switch. You will land on the car, because if you picked one of the wrong doors, they're going to have to show the other wrong door, and so if you switch, you're going to end up on the right answer. So what is the probability of winning if you always switch?