Suppose ABC Consulting Ltd is interested in finding out how long newly hired MBA graduates remain on their first jobs. It is common belief that MBA graduates stay on their jobs for 3 years before moving to another job. ABC Consulting wants to prove that CUD MBA graduates stay in their jobs more than 3 years. You have been tasked to do some research and on the basis of a small sample of employees with MBAs, you wish to estimate the population mean with 95 percent confidence. The data from the sample are presented below.

Number of years on first job: 3 5 7 1 12 1 2 5

a) Define the aim of this little research project. (1 Mark)

b) Write down a hypothesis that can be tested in this research. (1 Mark)

c) Determine the test statistic (z-value) based on the data given (6 Marks)

mean =

std dev =

std error =

z =

d) What is the p-value based on the data (2 Marks)

e) Interpret and explain your result (1 Mark)

f) Using the z-table, calculate the confidence interval (Lower and Upper) limits of the population mean at 95% confidence level. (2 Marks)

g) Interpret your results above (i.e. what does your result suggest in terms of 95% confidence level) (1 Mark)

g) Assuming that ABC Consulting accepts the range of error as 1.1, what would be the necessary sample size required for the survey? (1 Mark)