Refer to the Minitab display to the right. The probabilities were obtained by entering the values of n=5 and p equals p=0.198. In a clinical test of adrug, 19.8% of the subjects treated with 10 mg of the drug experienced headaches. In eachcase, assume that 5 subjects are randomly selected and treated with 10 mg of the drug. Find the probability that at least four of the subjects experience headaches.

x P(X=x)

0 0.3318

1 0.4096

2 0.2022

3 0.0499

4 0.0062

5 0.0003

The probability that at least four of the subjects experience headaches is