An IAB study on the state of original digital video showed that original data video is becoming increasingly popular. Original digital video is defined as professionally produced video only for ad-supported online distribution and viewing (not TV). According to IAB data, 26% of American adults 18+ watch original digital videos each month.

Source: Data extracted from “IAB Original Digital Video Consumer Study,” May 2016, bit.ly/2aUPkzk.

a. Suppose that you take a sample of 100 U.S. adults. If the population proportion of U.S. adults who watch original digital videos is 0.26, what is the probability that fewer than 21% in your sample will watch digital videos?

b. Suppose that you take a sample of 500 U.S. adults. If the population proportion of U.S. adults who watch original digital videos is 0.26, what is the probability that fewer than 21% in your sample will watch digital videos?

c. Discuss the effect of sample size on the sampling distribution of the proportion in general and the effect on the probabilities in (a) and (b).