 This is a binomial experiment. We have a sample of size n and the probability of an event of interest p of 5%. And we want to find the binomials probabilities for the occurrence of x equals 0, x equals 1, x equals 2, through x equals 10. When I click in this cell, we use the binomial.dist formula. By how like that, you can see that the first parameter there is x itself. And then n, the number of trials, p, the probability, and false. False gives the probability of exactly x happening in n trials. If we put true, that gives the sum of the probabilities from left infinity to x. For example, if we had x of 3, and we used the false flag, then that would give us the probability of 3 or less successes. In this formula, I want to be able to copy it down, so I need to lock down some things. b7, which is the x, is going to be changing, but b3 and 4, I want to lock down. So I want to put my cursor there, hit f4, hit the double dollar signs, and then f4 again, double dollar signs. Now I can drag this down, and I get my probabilities for one success in 100 trials, all the way to 10 successes in 100 trials. We then want to calculate the expected value of that series of events. We use just a simple formula, x times the probability to get that value, and then sum those up at the bottom to get the expected value. Here, the expected value of those various outcomes in 100 trials would be 4.87.