Question

Mrs. Wheeler prepares a list of 43 US presidents, 31 of whom served in the military. Then 8 students each select a president at random (there can be repeats) for their civics presentations. What is the probability that at least one of the students will select a president who did not serve in the military?

Answer 1

0.93

Explanation:

Answer 2

Explanation:

Given that Mrs. Wheeler prepares a list. The list consists of 43 US presidents out of which 31 served in the military. Remaining 12 no military service.

Now 8 students each select a president at random.

Let X be the no of persons selected who did not serve in military.

X is a random variable with two outcomes non military or military.

Each student is independent of selecting hence X is binomial

X:B(n = 8, p = 12/43)

q = 1-p = 31/43

Probability that at least one of the students will select a president who did not serve in the military = 1-Probability that noone of the students will select a president who did not serve in the military

=P(X≥1)=

= 1-P(X=0)

=
`1-((31)/(43))^8\\ = 0.9270`