In order to study any possible relationship between age and change in systolic blood pressure (BP) (mm Hg) in 24 hours in response to a treatment, the following data were obtained from 11 individuals.
|
Age
|
70
|
51
|
65
|
70
|
48
|
70
|
45
|
48
|
35
|
48
|
30
|
|
Systolic BP change
|
-28
|
-10
|
-8
|
-15
|
-8
|
-10
|
-12
|
3
|
1
|
-5
|
5
|
(a) Draw a scatterplot.
(b) Find the sample correlation of age and systolic BP.
(c) Fit a least-squares regression line.
(d) Interpret (a), (b), and (c).