Basic Mathematics for College Students

622 Chapter 7 Summary and Review

A bar graphpresents data using vertical or

horizontal bars. A horizontal axisand vertical

axis serve to frame the graph and they are

scaled in units such as years, dollars, minutes,

pounds, and percent.

CANCER DEATHS Refer to the bar graph below. How many more

deaths were caused by lung cancer than by colon cancer in the United

States in 2007?

From the graph, we see that there were about 160,000 deaths caused by

lung cancer and about 50,000 deaths from colon cancer. To find the

difference, we subtract:

160,000 – 50,000 = 110,000

There were about 110,000 more deaths caused by lung cancer than

deaths caused by colon cancer in the United States in 2007.

50,000

0

100,000

Number of deaths

150,000

200,000

Colon

Source: Lung Cancer Alliance

Breast Prostate Liver Kidney Lung

U.S. Cancer Deaths, 2007

To compare sets of related data, groups of two

(or three) bars can be shown. For double-baror

triple-bar graphs,a key is used to explain the

meaning of each type of bar in a group.

SEAT BELTS Refer to the double-bar graph below. How did the

percent of male high school students that rarely or never wore seat

belts change from 2001 to 2007?

From the graph, we see that in 2001 about 18% of male high school

students rarely or never wore seat belts. By 2007, the percent was about

14%, a decrease of 18% 14%, or 4%.

2007

2001

Year

4% 8% 12%

Source: The World Almanac, 2003, 2009

16% 20%

Male

Female

Risk Behaviors in High School Students

Percent that rarely or never wear seat belts

A pictographis like a bar graph, but the bars

are made from pictures or symbols. A keytells

the meaning (or value) of each symbol.

MEDICAL SCHOOLS Refer to the pictograph below. In 2008, how

many students were enrolled in California medical schools?

= 1,000 medical students

California

Missouri

Virginia

Total Medical School Enrollment

by State, 2008