4.3 Exercise 14

According to a poll, 60 percent of American adults prefer saving over spending. Let X = the number of American adults out of a random sample of 50 who prefer saving to spending.

1. What is the probability distribution for X?
2. Use your calculator to find the following probabilities:
   1. The probability that 25 adults in the sample prefer saving over spending
   2. The probability that at most 20 adults prefer saving
   3. The probability that more than 30 adults prefer saving
3. Using the formulas, calculate the (i) mean and (ii) standard deviation of X.