Anew drug on the market is known to cure 24% of patients with colon cancer. if a group of 15 patients is randomly selected, what is the probability of observing, at most, two patients who will be cured of colon cancer?

15 choose 2(0.24)2(0.76)13
15 choose 0(0.76)15 + 15 choose 1(0.24)1(0.76)14 + 15 choose 2(0.24)2(0.76)13
1 − 15 choose 2(0.24)2(0.76)13
15 choose 0 (0.76)15
1 − 15 choose 0 (0.76)15