Question

Compute y(7) from the following data :x : 8 10 12 14 16 18y : 10 9 32.5 54 89.5 15.4​

Answer 1

X: 8 10 12 14 16 18

Y: 10 9 32.5 54 89.5 15.4

x=X-X(bar)

X(bar) = 78/6 = 13

Y(bar) = 210.4/6 = 35

I have attached the table in an image form as it wasn't fitting in this tab.

$b_{yx} = \dfrac{\sum xy}{\sum x^2}$

$b_{yx} = \dfrac{290}{70} = 4.142$

Regression equation of Y on X is,

$(Y-\bar{Y}) =b_{yx}(X-\bar{X})$

$(Y-35) =4.142(X-13)$

Y - 35 = 4.142X - 53.846

Y = 4.142X - 53.846 + 35

Y = 4.142X - 18.846

Y (7) = 4.142 (7) - 18.846

Y (7) = 28.994 - 18.846

Y (7) = 10.148