8. Julie is a waitress. On the left is a log of her tips for yesterday’s shift.
a. Find the equation of the linear regression line. Round the slope
and y-intercept to the nearest hundredth.
b. What is the slope of the linear regression line?
c. What are the units of the slope when it is expressed as a rate?
d. Based on the linear regression line, what tip would Julie receive if
the restaurant bill were $120? Round to the nearest dollar.
e. Is your answer to part d an example of interpolation or extrapola-
tion? Explain.
f. Find the correlation coeffi cient for this data. Round to the near-
est hundredth.
g. Describe the correlation.
h. Based on the linear regres-
sion line, Julie creates a
spreadsheet to compute
predicted tips for any restau-
rant bill amount. Write the
formula that can be used to
compute the predicted tips
in column B.
Amount of
Restaurant Bill ($)
Tip
Amount ($)
45.55 7.00
52.00 15.00
66.00 6.00
24.44 6.00
57.90 15.00
89.75 23.00
33.00 8.00