And so the probability of picking an unfair coin and getting four heads in a row is going to be equal to 3 4ths times all of this business over here. So that's 3 4ths times, and this is 0.55 times itself four times. So I could write it as 0.55 to the fourth power. And we'll get the calculator out in a second to actually calculate what this is. Now, let's do the same thing for the fair coin. If I did pick a fair coin, the probability of getting heads four times in a row is going to be 0.5 times 0.5 times 0.5 times 0.5. Or the probability of getting the fair coin, which is 1 4th chance, times the probability and getting four heads in a row is going to be 1 4th times all of this.