Answer:
a) r = 0.13194
b) There is weak positive relationship between X and Y.
c) Slope () = 34.8333
d) Intercept ( = -132.333
e) y = -132.33 + 34.83 x
f) the predicted sales of tires be if he spends five thousand dollars in advertising = 41.82 - (in thousands of tires)
Step-by-step explanation:
a) By the coefficient of determination, the formula is:
r = ,
n = 6. Other values are provided too. Just substitute and obtain the value of r.
b) For correlation interpretation:
-1 ≤ r ≤ 1,
The closer the value to 1 the strong the relationship. If close to -1, there is strong negative relations and if close to +1, there is strong positive relationship. when the value is close to 0, there is weak positive relationship.
c) Slope is given as:
, and
d) Intercept is given as:
e) We obtain , therefore, the estimated Regression equation:
y = -132.33 + 34.83 x
f) Since the values are given is thousands of dollar. Then 5000 dollars is simply 5. We substitute the value into <em>x</em> in the regression equation and we have:
y = -132.33 + 34.83*(5) = 41.82