Sampling Distribution

I have a question that I don't quite understand how to answer even after looking at the section in my book that goes with the problem and reading over it several times.

Anyway, here is the question:

In a simple random sample of 1000 households, 150 households happen to own a barbecue grill. Based on the characteristics of the population, the expected number of grill owners in the sample was 180. What are the values of pi, p, and n?

Thanks much.
Well, never mind, I figured out the answers after thinking this problem through again for about the 15th time. LOL The answers are pi=.18, p=.15, n=1000. If anyone sees this problem and are using Introduction to Business Statistics by Ronald M. Weiers Fifth edition this would be the solution to problem 8.3 in Chapter 8. Maybe that will help someone else.