So it becomes a little bit more complicated. But there is an easy way to think about it where you could use this methodology right over here. You'll actually see this on a lot of exams where they make it seem like a harder problem, but if you just think about it the right way, all of a sudden it becomes simpler. One way to think about it is the probability of at least one heads in three flips is the same thing as the probability of not getting all tails. If we got all tails, then we don't have at least one head. So these two things are equivalent. The probability of getting at least one head in three flips is the same thing as the probability of not getting all tails in three flips.