If n = 8, ∑x = 2, ∑y = 0.2, ∑xy = 0.05, and ∑x2 = 5, then one of the normal equations for y = a + bx is

Question

I Am really having a hard time with this question, Help PLEASE would the answer be 8a+2b=0.2??

Answer 1

For n=8 

 

8X=2 

 so X = 2/8 =1/4

 

8Y =0.2 

 

So Y = 0.2 /8

Y  = 2/80

   =1/40

 

8XY =0.05

 

Now using X = 1/8

and Y = 1/40 in eqation Y =a+bX    1/40 = a+b(1/4) Th en multiplying by 8 Gives 8a+2b =0.2 Ans

 

The remaining two expression 8XY =0.05  is also true  for the calculated values of X and Y . The last 8 ( X2) is not understood . Some thing wrong with the expression