The Smith family has twins, Rob and Rachel. Both Rob and Rachel graduated from college two years ago, and each is now earning $50,000 per year. Rachel works in the retail industry, where the mean salary for executives with less than 5 years' experience is $35,000 with a standard deviation of $8,000. Rob is an engineer. The mean salary for engineers with less than 5 years' experience is $60,000 with a standard deviation of $5,000.
a. Compute the z values for both Rob and Rachel.
b. Comment on your findings
The solution contains detailed explanation of finding the z values if the standard deviation of a population is given.