7th Grade Math

516 Statistical Displays

Analyze a Circle Graph

AUTOMOBILES The graph shows

the percent of automobiles

registered in the western United

States in a recent year.

Which state had the most

registered automobiles?

The largest section of the circle

is the one representing

California. So, California has the

most registered automobiles.

If 24 million automobiles were registered in these states, how many

more automobiles were registered in California than in Oregon?

California: 78% of 24 million 0.78 × 24, or 18.72 million

Oregon: 6% of 24 million 0.06 × 24, or 1.44 million

There were 18.72 million - 1.44 million, or 17.28 million more

registered automobiles in California than in Oregon.

c. Which state had the least number of registered automobiles?

Explain.

d. What was the total number of registered automobiles in

Washington and Oregon?

U.S. Registered Automobiles

in West

Washington

Oregon 13%

6%

Nevada

3%

California

78%

Examples 1 and 2 Display each set of data in a circle graph.

1. Blood Types in the U.S.
   Blood Type Percent
   O44
   A42
   B10
   AB 4
   2. Favorite Musical Instrument
   Type Number of Students
   Piano 54
   Guitar 27
   Drum 15
   Flute 24

Examples 3 and 4 3. COLORS Use the graph that shows the results

of a survey.

a. What color is most favored?

b. If 400 people were surveyed, how many

more people favored purple than red?

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1VSQMF



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Favorite Color

Check for Reasonableness

To check Example 4, you

can estimate and solve the

problem another way.

78% - 6% ≈ 70%

70% of 24 is 17

Since 17.28 is about 17, the

answer is reasonable.

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