Question

A volleyball player’s serving percentage is 90%. Six random serves are selected. What is the probability that 5 of those serves were successful?

0.09
0.35
0.59
0.90

Answer 1

C (.35) on edge2021! :)

Explanation:

for this problem we use the formula P(X = k) = (n over k)p^k(1-p)^n-k and in this case,

k = 5

n = 6

p = .90

and (n over k), n choose k, is calculated by (n! / k!(n-k)!) or just look up "6 choose 5" and you'll figure out that it's equal to 6.

so you end up with P(X = 5) = 6(.90)^5(1-.90)^6-5 which will give you .35 when put in a calculator.