According to a survey in December 2018 of Women on Boards, women hold 21.7% of director seats on U.S. corporate boards. This study also reports that 39.2% of U.S. companies have three or more female board directors.
If you select a random sample of 200 U.S. companies,
a. What is the probability that the sample will have between 30% and 38% companies that have three or more female board directors?
b. The probability is 90% that the sample percentage of companies that have three or more female board directors will be contained within what symmetrical limits of the population percentage?
c. The probability is 95% that the sample percentage of companies that have three or more female board directors will be contained within what symmetrical limits of the population percentage?