7. [1.41/1.88 Points]
DETAILS
MY NOTES
ASK YOUR TEACHER
PRACTICE ANOT
How much should a healthy Shetland pony weigh? Let x be the age of the pony (in months), and let y be the average weight of the pony (in kilograms).
x | 3 | 6 | 12 | 14 | 26
y | 60 | 95 | 140 | 158 | 181
USE SALT
(a) Make a scatter diagram of the data and visualize the line you think best fits the data.
y (average weight (in kg))
180
160
140
120
100
80
60
5
10
15
20
25
x (age (in months))
y (average weight (in kg))
180
160
140
120
100
80
60
5
10
y (average weight (in kg))
25
20
15
10
5
60
80
100
120
140
160
180
x (age (in months))
y (average weight (in kg))
25
20
15
10
5
60
80
100
120
140
160
180
x (age (in months))
(b) Would you say the correlation is low, moderate, or strong? positive or negative?
strong and positive
low and negative
moderate and negative
low and positive
strong and negative
moderate and positive
(c) Use a calculator to verify that $\sum x = 61$, $\sum x^2 = 1,061$, $\sum y = 634$, $\sum y^2 = 89,950$, and $\sum xy = 9,348$.
Compute r. (Round your answer to four decimal places.)
r =
As x increases from 3 to 26 months, does the value of r imply that y should tend to increase or decrease? Explain your answer.
Given our value of r, y should tend to remain constant as x increases.
Given our value of r, we can not draw any conclusions for the behavior of y as x increases.
Given our value of r, y should tend to increase as x increases.
Given our value of r, y should tend to decrease as x increases.
