That's the probability of it's going to be 1 half, because you have a 1 half chance of getting a tails on the first flip, times, let me write it here so it becomes a little clearer, so this is going to be 1 minus the probability of getting all tails, well, you have a 1 half chance of getting tails on the first flip, and then you're going to have to get another tails on the second flip, and then you're going to have to get another tails on the third flip. And then 1 half times 1 half times 1 half, this is going to be 1 eighth. And then 1 minus 1 eighth, or 8 eighths minus 1 eighth, is going to be equal to 7 eighths. So we can apply that to a problem that is harder to do than writing all of the scenarios like we did in the first problem, we can say, let's say we have 10 flips, the probability of at least 1 head in 10 flips. Well, we use the same idea, this is the same thing, this is going to be equal to the probability of not all tails in 10 flips. So we're just saying the probability of not getting all of the flips going to be tails, all of the flips is tails, not all tails in 10 flips. And this is going to be 1 minus the probability of flipping tails 10 times.