The following data relates to the scores obtained by 9 salesmen of a company in an intelligence test and their weekly sales in thousands of Rs.
Salesmen:
A
B
C
D
E
F
G
H
I
Test score :
50
60
50
60
80
50
80
40
70
Weekly sales :
30
60
40
50
60
30
70
50
60
Obtain the regression equation of sales on test scores of the salesmen and estimate sales if the test score of a salesman is 65.