A small firm negotiates an annual pay rise with each of its twelve employees. In an attempt to simplify the process it is proposed that each employee should be given a score (x) based on his/her level of responsibility. The annual salary (y) will be fla+ bx) and the annual negotiations will only involve the values of a and

b. The following table gives last year's salaries (which were generally accepted as fair) and the proposed scores. 13- Annual salary Employee x (), y A 10 5 750 B 55 17 300 46 14 750 27 8 200 17 6 350 12 6 150 18 800 64 14 850 36 9 990 40 11 000 30 9 150 37 10 400 (You may assume that Ex-459, Ex-22 889, Ey-132 600, Exy-6 094 750)

(a) Plot the data on a scatter diagram..

(b) Estimate values that could have been used for a and b last year by fitting the regression line y-a+ bx to the data. Draw the line on the scatter diagram.

(c) Comment on whether the suggested method is likely to prove reasonably satisfactory in practice. minn line find