Answer:
0.1745
Step-by-step explanation:
We are given the following information:
We treat alumni contacted by telephone making a contribution of at least $50 as a success.
P(Alumni making a contribution) = 80% = 0.8
Then the number of alumni follows a binomial distribution, where
where n is the total number of observations, x is the number of success, p is the probability of success.
Sample size, n = 20
We have to evaluate:
Thus, 0.1745 is the probability that exactly 15 alumni will make a contribution of at least $50 when contacted by telephone.