If you have a calculator with statistical functions, that's the way to go.
On my TI-83, I typed in invNorm(0.88) and got the result z = 1.17.
88% of the area under the normal curve is to the left of z = 1.17.
Answer:
a= 13.15 years
b= -0.62 years/$
Step-by-step explanation:
Hello!
Given the variables
Y: Age of a used car. (years)
X: Price of a sold used car. ($000)
The linear regression model is:
E(Y)= α + βXi
The estimated equation is:
^Y= a + bXi

a= 13.15 years

b= -0.62 years/$
Then ^Y= 13.15 - 0.62Xi
Mean Y= 8.92
Mean X= 6.91
∑Y= 107
∑Y²=1009
∑X=82.90
∑X²=615.29
∑XY=712.9
Hope it helps!