Main Idea and New Vocabulary Example 1: Display Data in a Circle Graph Example 2: Construct a Circle Graph Example 3: Analyze a Circle Graph Example 4: Analyze a Circle Graph Lesson Menu

Construct and analyze circle graphs. Main Idea/Vocabulary

Display Data in a Circle Graph COMMUNITY SERVICE In a survey, a group of middle-school students were asked to name their favorite community service activity. The results are shown in the table. Display the data in a circle graph. Example 1

Display Data in a Circle Graph ● There are 360 in a circle. Determine what part of the circle will represent each percent from the table. 18% of 360 = 0.18  360 or 65 Round to the nearest whole degree. 26% of 360 = 0.26  360 or 94 31% of 360 = 0.31  360 or 112 9% of 360 = 0.09  360 or 32 16% of 360 = 0.16  360 or 58 Example 1

Display Data in a Circle Graph ● Draw a circle with a radius as shown. Then use a protractor to draw the first angle, in this case 65. Repeat this step. Example 1

Display Data in a Circle Graph ● Label each section of the graph with the category and percent. Give the graph a title. Answer: Example 1

Display Data in a Circle Graph Check 65 + 94 + 112 + 32 + 58 = 361  Because of rounding the sum of the degrees is 361°. Example 1

In a survey, a group of elementary students were asked what kind of pets they have, if any. The results are shown in the table. Display the data in a circle graph. A. B. C. D. Example 1 CYP

Construct a Circle Graph MUSIC Ryan has the following types of CDs in his music collection. Make a circle graph of the data. Example 2

Construct a Circle Graph ● Find the total number of CDs. 48 + 37 + 13 + 6 = 104 ● Find the ratio that compares each number with the total. Write the ratio as a decimal rounded to the nearest hundredth. Example 2

Construct a Circle Graph ● Find the number of degrees for each section of the graph. Rock: 0.46  360  166 Hip-Hop: 0.36  360  130 Alternative: 0.13  360  47 Country: 0.06  360  22 ● Draw the circle graph. Label each piece with the title and percent. Example 2

Construct a Circle Graph Answer: Check After drawing the first three sections, you can measure the last section of a circle graph to verify that the angles have the correct measures. Example 2

Julie has the following types of soda in her refrigerator Julie has the following types of soda in her refrigerator. Make a circle graph of the data. A. B. C. D. Example 2 CYP

Analyze a Circle Graph POPULATION The graph shows the percent of population in the five largest cities in Florida. Which city has the least percent of population? Answer: The smallest section of the circle is the one representing Orlando. So, Orlando has the least percent of population. Example 3

AUTOMOBILES The graph shows the percent of vehicle types in a parking lot. Which type of vehicle makes up the largest percent of the total vehicles? A. bicycles B. trucks C. motorcycles D. cars Example 3 CYP

Analyze a Circle Graph POPULATION The graph shows the percent of population in the five largest cities in Florida. If the total population of these five cities is 2 million people, how many more people live in Miami than Tampa? Example 4

Miami: 20% of 2 million  0.20  2, or 0.40 million Analyze a Circle Graph Miami: 20% of 2 million  0.20  2, or 0.40 million Tampa: 17% of 2 million  0.17  2, or 0.34 million 0.40 million – 0.34 million = 0.06 million Answer: There are 0.40 million – 0.34 million = 0.06 million or 60,000 more people living in Miami than in Tampa. Example 4

AUTOMOBILES The graph shows the percent of vehicle types in a parking lot. If there are 200 vehicles in the parking lot, how many more cars are there than bicycles? A. 130 more cars B. 120 more cars C. 60 more cars D. 5 more cars Example 4 CYP