X                           Y      X.Y     X.
X
 3                           55     165     9
 12                          40     480     144
 6                           55     330     36
 20                          10     200     400
 14                          15     210     196
 =14                         =175   =1385   =196
TO FIND A:
    ∑ Y . ∑ X 2−∑ X . ∑ XY
=
       N . ∑ X 2−(∑ X )2
    175.785−55.1385
=
       5.785−552
= 68
TO FIND B:
N . ∑ X Y −∑ X .∑ Y
         2       2
 N . ∑ X −(∑ X )
5.1385−55.175
            2
 5.785−( 55)
= -3
A AND B REGRESSION FORMULA
Y= A+B.X
Y= 68-3.X
REPLACE X BY 10
Y= 68-3(10)
Y=68-30
Y=38