Using the binomial distribution, it is found that Sam should have expected 5 people to say yes.
The formula is:
[tex]P(X = x) = C_{n,x}.p^{x}.(1-p)^{n-x}[/tex]
[tex]C_{n,x} = \frac{n!}{x!(n-x)!}[/tex]
The parameters are:
The expected value is given by:
E(X) = np.
In this problem:
Hence, the expected value for the number of people that say yes is given by:
E(X) = np = 15 x 0.32 = 5.
More can be learned about the binomial distribution at https://brainly.com/question/24863377