Oakland Terrace Math 7 (Math A)

Ms. Shane's Class looked at data presented in the news. They noticed that a lot of data is presented to readers during the presidential election cycle. They noticed that data is presented in graphs and tables. Students took the data from these tables about the Ohio and Texas Presidential Primaries, and turned them into circle graphs.

Circle Graph showing the Age Ranges of Democratic Voters in Ohio

This student turned the percentages from the table above into a bar graph. She needed to find the angles of each section of the circle. She turned each percentage into a decimal value, and multiplied by 360º to figure out how to construct the circle graph.

28%	.28 x 360º = 101º
16%	.16 x 360º = 58º
34%	.34 x 360º = 122º
22%	.22 x 360º = 79º

	This student converted percentages from a survey of Texas Democratic sentiment into a circle graph. She had to compute the angle measurements of each of the segments to represent the correct ratio of the circle for each category.

		Students also discovered that the Sports section shows a lot of data. Students converted NHL teams' records into circle graphs showing the teams' winning percentages. Detroit has a very high percentage of its games that resulted in victory at 65 %.

Circle Graph showing the Detroit Nashville's Record

Wins	33	33/66 = 50%
Losses	25	25/66 = 38%
OT Losses	8	8/66 = 12 %
Total Games	66	100%

First the student figured out the percentage of the team's games that ended in a win, a loss, or an overtime loss, which determine the hockey standings. The ratio of wins, losses and overtime losses to total games was converted into a percentage, etc.

50%	180º
38%	137º
12%	43º
Total	360º

The student then converted the percentages into the ratio of the circle representing each category by determining the angle measurement.

Indicators 6.7.7.2 use strategies to solve problems involving ratios, proportions, and percents. 4.7.2.2 draw circle graphs using ratios, proportions, and percents.