correlation amd regression

[abhinav619]

The two regression equations of X and Y and Y on X are given
Y= 100.26+0.77X
X=1.28Y-143.7

Find the means of X and Y

[Akshay Jain]

The two regression equations passes thru the mean values of X and Y
so solve these two equations simultaineously and get the values of Xbar and Ybar
...

[Anjali]

Akshay could you please elaborate ?

[Akshay Jain]

Just look at the 1st normal equations of both the regression equations Y on X and X on Y
Ybar=Beta1+Beta2*Xbar
and
Xbar=alpha1+alpha2*Ybar
since both the equations vl pass through Xbar and Ybar (mean values)
solve these equations simultaineously to get these values...
is this enough @anjali???

[Anjali]

You mean that we just have to replace X and Y with Xbar and Ybar , and then solve these two equations simultaneously . Is that so ?

[E A Ibrahim]

Mean of X= 779.77
Mean of Y= 721.46

[Akshay Jain]

You got it
....

[abhinav619]

I am not getting via this method. The correct answers are

X(mean) = -1067.17
Y(mean) = -721.46