Sampling at a party. At a large block party there are 40 men and 30 women. You want to ask opinions about how to improve the next party. You choose at random 4 of the men and separately choose at random 3 of the women to interview.

(a) What is the probability that any of the 40 men is in your random sample of 4 men to be interviewed? What is the probability that any of the 30 women is in your random sample of 3 women to be interviewed?

(b) If you have done the calculations correctly in part (a), the probability of any person at the party being interviewed is the same. Why is your sample of 7 men and women not an SRS of people from the party?

(C) Say you know that 20 of the 70 people in the party are from out of town, but you don't know which 20 people. To get the opinions of people across different locations, you randomly select people from the 70 and ask them if they're from out of town or not. If you keep sampling people until you have 2 from out of town and 5 from in town, what sort of sampling method are you using?