Answer:
a) ![r=\frac{9(396)-(18)(153)}{\sqrt{[9(51) -(18)^2][9(3141) -(153)^2]}}=1](https://tex.z-dn.net/?f=r%3D%5Cfrac%7B9%28396%29-%2818%29%28153%29%7D%7B%5Csqrt%7B%5B9%2851%29%20-%2818%29%5E2%5D%5B9%283141%29%20-%28153%29%5E2%5D%7D%7D%3D1) 
  
We have a perfect linear relationship between the two variables 
b)  
  
Nowe we can find the means for x and y like this:  
 
  
 
  
And we can find the intercept using this:  
 
  
So the line would be given by:  
 
  
c) For this case the slope indicates that for each increase of the number of hours in 1 unit we have an expected increase in the score about 6 units.
And the intercept 5 represent the minimum score expected for any game 
Step-by-step explanation:
We have the following data:
Number of hours spent practicing (x) 0 0.5 1 1.5 2 2.5 3 3.5 4 
Score in the game (y) 5 8 11 14 17 20 23 26 29 
Part a
The correlation coefficient is given:
![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=9  
  
![r=\frac{9(396)-(18)(153)}{\sqrt{[9(51) -(18)^2][9(3141) -(153)^2]}}=1](https://tex.z-dn.net/?f=r%3D%5Cfrac%7B9%28396%29-%2818%29%28153%29%7D%7B%5Csqrt%7B%5B9%2851%29%20-%2818%29%5E2%5D%5B9%283141%29%20-%28153%29%5E2%5D%7D%7D%3D1) 
  
We have a perfect linear relationship between the two variables 
Part b
 
  
Where:  
 
  
 
  
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:  
 
  
So the line would be given by:  
 
  
Part c
For this case the slope indicates that for each increase of the number of hours in 1 unit we have an expected increase in the score about 6 units.
And the intercept 5 represent the minimum score expected for any game