You are interested in determining the average number of social media accounts people have. You interview 30 people at random and the number of social media accounts they have has a sample mean of 7.1 and a sample standard deviation of 2.09.

a) Define the parameter of interest.

b) State and check if the assumptions needed for constructing the appropriate CI for the parameter of interest are satisfied.

c) Find a 90% confidence interval for the parameter defined in part a). Use the table, not the calculator to find the appropriate critical value.

d) Write sentence to interpret the CI computed in part c).