Study Guide and Intervention (continued) - MathnMind

5-7
NAME ______________________________________________ DATE ____________ PERIOD _____
Study Guide and Intervention
Scatter Plots and Lines of Fit
Interpret Points on a Scatter Plot A scatter plot is a graph in which two sets of
data are plotted as ordered pairs in a coordinate plane. If y increases as x increases, there is
a positive correlation between x and y. If y decreases as x increases, there is a negative
correlation between x and y. If x and y are not related, there is no correlation.
Example
EARNINGS The graph at the right
shows the amount of money Carmen earned each
week and the amount she deposited in her savings
account that same week. Determine whether the
graph shows a positive correlation, a negative
correlation, or no correlation. If there is a
positive or negative correlation, describe its
meaning in the situation.
The graph shows a positive correlation. The more
Carmen earns, the more she saves.
Exercises
Determine whether each graph shows a positive correlation, a negative
correlation, or no correlation. If there is a positive correlation, describe it.
1. 2.
Average Weekly Work Hours in U.S.
Hours
3. 4.
Growth of Investment Clubs
Number of Mutual Funds
Number of Clubs
(thousands)
35
28
21
14
7
y
34.8
34.6
34.4
34.2
0 1 2 3 4 5 6 7 8 9 x
Years Since 1990
Source: The World Almanac
0 1 2 3 4 5 6 7 8
Years Since 1990
Source: The Wall Street Journal Almanac
Average Jogging Speed
0 1 2 3 4 5 6 7
Years Since 1991
© Glencoe/McGraw-Hill 317 Glencoe Algebra 1
Number of Funds
(thousands)
Miles per Hour
10
5
0 5 10 15 20 25
Minutes
7
6
5
4
3
Carmen’s Earnings and Savings
Dollars Saved
35
30
25
20
15
10
5
Source: The Wall Street Journal Almanac
0 40 80 120
Dollars Earned
Lesson 5-7