A department store would like to develop a model to estimate the sales performance target score of their sales staff given their sales aptitude test score.A random sample of 5 salespersons is selected with the following results:

Sales Performance Target Score (Y)

92

77

83

72

81

Sales Aptitude Test Score (X)

70

57

65

55

62

(a)Determine the correlation coefficient.

(b)Interpret the correlation coefficient.

(c)Determine the regression line.

(d)Interpret the regression coefficients.

(e)Estimate the change in performance target score if a sales staff's aptitude score improved by 10 marks.

(f)Estimate the performance target score if a sales staff's aptitude score is 60.