binomial probability

Question

the management of a restaurant conducted a survey and found that 35% of the customers preferred to sit in the smoking section. based on this information, what is the probability that for a random sample of 11 customers, 4 preferred the smoking section?

Answer 1

formula for binomial probability:

probability x successes in n independent trials, where each trial has the probability p of success:

P(x;n;p) = n!

---- * p^x * (1-p)^(n-x)

x!(n-x)!

For this problem p = 0.35 and n = 11, x = 4.