Question

An investment firm wants to estimate their average return on investment, so they can advertise it to new clients. Based on a sample of 21 clients, they obtain a sample mean of 6.7%. From historical data, they know that the population standard deviation is 1.2%. Find a 95% confidence interval for the average return on investment. Round your answers to 1 decimal place (e.g. enter 6.7 for 6.7%)

___________ % (Lower Limit)

___________ % (Upper Limit)

Consumer protection regulations require truthful advertising. Which of the following claims could the investment firm make in their advertising?

Select your answer from one of the following options.

• a.95% of our clients earn between _____ and ______ return on investment.
• b.With 95% confidence, our average return on investment is between ______ and ______.
• c.Our average return on investment for all our clients is 6.7%.
• d.95% of our clients earn at least 6.7% return on investment.

Answer 1

95% confidence interval for the average return on investment.

6.2 % (Lower Limit)

7.2% (Upper Limit)

answer :
b.With 95% confidence, our average return on investment is between 6.2% and 7.2%

Explanation :

PL??