7.5 Other scenario for exit poll Refer to Examples 1 and 2 about the exit poll, for which the sample size was 3889. In that election, 40.9% voted for Whitman.

a. Define a binary random variable X taking values 0 and 1 that represents the vote for a particular voter

(1 = vote for Whitman and 0 = another candidate).

State its probability distribution, which is the same as the population distribution for X.

b. Find the mean and standard deviation of the sampling distribution of the proportion of the 3889 people in the sample who voted for Whitman.