7-4 Reading and Interpreting Circle Graphs Warm Up Warm Up Lesson Presentation Lesson Presentation Problem of the Day Problem of the Day Lesson Quizzes

7-4 Reading and Interpreting Circle Graphs

Warm UpWarm Up

Lesson PresentationLesson Presentation

Problem of the DayProblem of the Day

Lesson QuizzesLesson Quizzes


Warm UpWrite each fraction as a percent.

1. 2. 3.

Write each percent as a fraction.

4. 20% 5. 25% 6.60%

75% 10% 40%34

110

25

15

14

35


Problem of the Day

Riddle: When does 1 + 1 + 1 = 1?1 ft + 1 ft + 1 ft = 1 yd


MA.7.S.6.2 Construct and analyze…circle graphs.

Sunshine State Standards


Vocabulary

circle graphsector


A circle graph, also called a pie chart, shows how a set of data is divided into parts.

The entire circle contains 100% of the data.

Each sector, or slice, of the circle represents one part of the entire data set.


The circle graph compares the number of species in each group of echinoderms. Echinoderms are marine animals that live on the ocean floor.


Use the circle graph to answer the question.

Additional Example 1A: Life Science Application

Which group of echinoderms includes the fewest number of species?

The sector for sea lilies and feather stars is the smallest, so this group includes the fewest number of species.


Use the circle graph to answer the question.

Additional Example 1B: Life Science Application

Approximately what percent of echinoderm species are brittle stars and basket stars?

about , so approximately 33%

13


Use the circle graph to answer each question.

Check It Out: Example 1A

Which size car sold the most?

Midsize

Small

LuxuryLarge

The sector for midsize cars is larger than any other of the sectors of car sizes. This means midsize cars were sold the most.



Check It Out: Example 1B

Approximately what percent of cars sold were midsize?

Midsize

Small

LuxuryLarge

The midsize sector is approximately half or about 50%.



Check It Out: Example 1C

Which size sold less—large or small?

Midsize

Small

LuxuryLarge

The smallest sector between Large and Small is Large. Large sized cars sold less.


Leon surveyed 30 people about pet ownership. The circle graph shows his results. Use the graph to answer each question.

Additional Example 2A: Interpreting Circle Graphs

How many people own dogs only?

The circle graph shows that 20% of the 30 people own dogs only.

20% of 30 = 0.2 • 30

= 66 people own dogs only.


Leon surveyed 30 people about whether they own pets. The circle graph shows his results. Use the graph to answer each question.

Additional Example 2B: Interpreting Circle Graphs

How many people own both cats and dogs?

Since 20% is 6 people, 10% is 3 people.

3 people own both cats and dogs.


Check It Out: Example 2A

Fifty students were asked which instrument they could play. The circle graph shows the responses. Use the graph to answer each question.

How many students do not play an instrument?

piano20%

no instrument50%

flute10%

drum20%

The circle graph shows that 50% of 50 students do not play an instrument.

50% of 50 = 0.5 • 50

= 25

25 students do not play an instrument.


Check It Out: Example 2B

Fifty students were asked which instrument they could play. The circle graph shows the responses. Use the graph to answer each question.

Ten students said they play the piano. How many play the flute?

Since 20% is 10 students, 10% is 5 students.

Five students play the flute. piano

20%

no instrument50%

flute10%

drum20%


A company reports its annual charitable contributions. Draw a circle graph to represent this data.

Additional Example 3: Drawing a Circle Graph

Step 1: Find the total dollars contributed.

120,000 + 60,000 + 120,000 + 96,000 + 84,000 = 480,000


Additional Example 3 Continued

Step 2: Find the percent each cause is to the whole.

Education and Health

Environment Disaster Relief

Arts & Humanties

Step 3: Multiply the percent times 360 (the total number of degrees in a circle) for each contribution to find the measure of the central angle.


Additional Example 3 Continued

Step 4: Use a protractor to draw each angle inside a circle. Label each wedge with the corresponding percent.


A group of track and field members are asked which event is their favorite. Draw a circle graph to represent this data.

Check It Out: Example 3

Step 1: Find the total number of members.

24 + 18 + 30 + 12 + 36 = 120


Check It Out: Example 3 Continued

Step 2: Find the percent each event is to the whole.

Sprints

Hurdles Jumping

Relay

Step 3: Multiply the percent times 360 (the total number of degrees in a circle) for each event to find the measure of the central angle.

Throwing


Check It Out: Example 3 Continued

Step 4: Use a protractor to draw each angle inside a circle. Label each wedge with the corresponding percent.


Standard Lesson Quiz

Lesson Quizzes

Lesson Quiz for Student Response Systems


Lesson Quiz: Part IUse the circle graph to answer questions 1-4.

1. Which group of CDs sold the most?

2. What percent of the CD sales are country?

3. Which type of CD sells the least?

4. If a total of 500 CD’s are sold, how many are Jazz?

rock

27%

rap

55

41%


Lesson Quiz: Part II

5. Would a bar or circle graph best display the sales of a department store for the last 5 months?

bar graph


1. The members of a club were asked to vote for their favorite holiday destination. The results are shown in the form of a circle graph. Which destination was preferred the most by the members?

A. PortugalB. FranceC. GreeceD. Spain



2. 300 students in a school play any one musical instrument. The circle graph shows what percentage of students play different instruments. How many students play guitar?

A. 15B. 36C. 96D. 144



3. Which of the following would be the best display for the nutritional value of a food item?

A. bar graphB. double bar graphC. histogramD. circle graph


Documents

7-4 Reading and Interpreting Circle Graphs Warm Up Warm Up Lesson Presentation Lesson Presentation Problem of the Day Problem of the Day Lesson Quizzes