Do exercise 3 using the ages instead of the salaries.
a. Find the population mean for salary.
b. Compare this population mean to the sample average for salary. In particular, how many standard errors apart are they?
c. Find the population standard deviation for salary and interpret this number.
d. Compare this population standard deviation to the sample standard deviation for salary.
e. Find the population standard deviation for the average salary for a sample and interpret this number. Compare it to the standard error from the sample salary data.
f. Arrange the numbers you have computed in a table where the columns are “population” and “sample” and the rows are “sample average and population mean,” “standard deviation of individuals,” and “standard deviation and standard error of sample averages of 10 employees.”