7th Grade Math

536 Statistical Displays

Use a Scatter Plot to Predict

NASCAR The scatter plot shows the earnings for the winning

driver of the Daytona 500 from 1996 to 2008. Predict the winning

earnings for the 2012 Daytona 500.

Daytona 500 Winnings

1994 1996 1998 2000 2002 2004 2006 2008 2010 2012

1.5

1

0.5

2

2.5

Earnings (millions $)

Year

The line of best fit

is close to most of

the data points.

The predicted winning earnings for 2012 will be about $2,000,000.

c. NASCAR Predict the winning earnings for 2014.

Examples 1 and 2 1. POPULATION Fayette County is a fast

Number of People

20002001200220032004200520062007

40,000

38,000

36,000

34,000

32,000

30,000

28,000

26,000

24,000

22,000

20,000

Year

growing county in Tennessee. The Population of Fayette County

graph shows its increase in population.

a. Describe the relationship between

the two variables.

b. Construct a line of best fit.

c. If the trend continues, what will be

the population in 2010?

Example 3 2. PICNICS The scatter plot shows the

number of people who attended a

neighborhood picnic each year. What

is the expected attendance for 2010?

Picnic Attendance

2005 2006 2007 2008 2009

Year

190

130

150

170

110

Number of People^90

Scatter Plots Another

name for scatter plot is

scattergram.

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