Answer:
a) 
b) 
c) ![r=\frac{7(30095)-(4210)(49)}{\sqrt{[7(2595100) -(4210)^2][7(354) -(49)^2]}}=0.7503](https://tex.z-dn.net/?f=r%3D%5Cfrac%7B7%2830095%29-%284210%29%2849%29%7D%7B%5Csqrt%7B%5B7%282595100%29%20-%284210%29%5E2%5D%5B7%28354%29%20-%2849%29%5E2%5D%7D%7D%3D0.7503)
Step-by-step explanation:
Data given
x: 500, 700, 750, 590 , 540, 650, 480
y: 7.00, 7.50 , 9.00, 6.5, 7.50 , 7.0, 4.50
Part a
We want to create a linear model like this :
Wehre
And:
With these we can find the sums:
And the slope would be:
Nowe we can find the means for x and y like this:
And we can find the intercept using this:
And the line would be:
Part b
The correlation coefficient is given by:
![r=\frac{n(\sum xy)-(\sum x)(\sum y)}{\sqrt{[n\sum x^2 -(\sum x)^2][n\sum y^2 -(\sum y)^2]}}](https://tex.z-dn.net/?f=r%3D%5Cfrac%7Bn%28%5Csum%20xy%29-%28%5Csum%20x%29%28%5Csum%20y%29%7D%7B%5Csqrt%7B%5Bn%5Csum%20x%5E2%20-%28%5Csum%20x%29%5E2%5D%5Bn%5Csum%20y%5E2%20-%28%5Csum%20y%29%5E2%5D%7D%7D)
For our case we have this:
n=7 
The determination coefficient is given by:
Part c
