BUS352 Chapter 7 Problems

7.1  Given a normal distribution with m = 100 and s = 10, if you select a sample of n = 25, what is the probability that X is

a. less than 95?

b. between 95 and 97.5?

c. above 102.2?

d. There is a 65% chance that X is above what value?

7.17  The Chartered Financial Analyst (CFA) Institute reported that 49% of its U.S. members indicate that lack of ethical culture within financial firms has contributed the most to the lack of trust in the financial industry. (Source: “Global Market Sentiment Sur-vey 2014,” cfa.is/Psk5O3.) Suppose that you select a sample of 100 CFA members.

a. What is the probability that the sample percentage indicating that lack of ethical culture within financial firms has contrib-uted the most to the lack of trust in the financial industry will be between 48% and 53%?

b. The probability is 90% that the sample percentage will be contained within what symmetrical limits of the population percentage?

c. The probability is 95% that the sample percentage will be contained within what symmetrical limits of the population percentage?

d. Suppose you selected a sample of 400 CFA members. How does this change your answers in (a) through (c)?