SOLUTION: "Suppose that the probability that any random freshman girl will agree to go with Sam to the senior prom is 0.1. Suppose Sam asks 10 random freshman girls to the prom. On average,

Algebra ->  Statistics  -> Binomial-probability -> SOLUTION: "Suppose that the probability that any random freshman girl will agree to go with Sam to the senior prom is 0.1. Suppose Sam asks 10 random freshman girls to the prom. On average,       Log On


   

Question 1073370: "Suppose that the probability that any random freshman girl will agree to go with Sam to the senior prom is 0.1. Suppose Sam asks 10 random freshman girls to the prom. On average, how many freshman girls will agree to go with Sam to the prom?"
I understand that n=10 and p=.1 but I don't understand how to figure out the average.
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
average is n * p = 10 * .1 = 1
standard error is sqrt(n * p * q) = sqrt(10 * .1 * .9) = .94868...

this is normal distribution of a proportion.

here's a reference.

"_blank">http://www.math.ubc.ca/~feldman/m302/binomial.pdf

lots of math in there, but the punch line is what's enclosed in the boxes.

mean = n * p.

variance = n * p * q

q = 1 - p

standard deviation is sqrt (n * p * q)