Question

If you flip three coins simultaneously, what's the probability you'll get three heads for the first time on the fifth toss?

Answer 1

In this question, you are flipping 3 coins simultaneously until you get all 3 heads, so we are looking at a binompdf, where x=5 (landing a success on the 5th trial), and p=0.5^3 (probability of success, meaning the probability of getting three heads). Plugging in to your calculator, binompdf(0.125,5)=0.0733