Question 3
The back-to-back stem-and-leaf diagram shows the annual salaries, in dollars, of 27 employees at each of two companies, Browns and Greens.

Key: 6|32| 7 means $ 32600 for Browns and $ 32700 for Greens.
Question 3(a)
Find the median and interquartile range for the annual salaries of employees at Browns.
Question 3(b)
The annual salary of an employee at Browns is denoted by x thousand dollars and the annual salary of an employee at Greens is denoted by y thousand dollars. It is given that, for the 27 employees at each of the companies, sum x=878.3, sum x^2=28616.09, sum y=896.5, sum y^2=29815.63. Find the mean and standard deviation of the annual salaries of these 54 employees.







