th grade math Using Circle Graphs

Objective To use circle graphs to solve problems Why? To know how to read a type of graph often used in newspapers and magazines.

California State Standards MR 2.4: Use a variety of methods, such as … graphs, … to explain mathematical reasoning. AF 1.1 : Write and solve one-step linear equations in one variable. MR 1.3: Determine when and how to break a problem into simpler parts. MR 2.2: Apply strategies and results from simpler problems to more complex problems MR 2.5: Express the solution clearly and logically by using the appropriate mathematical notation and terms and clear language; support solutions with evidence in both verbal and symbolic work.

A circle graph show how a whole is broken into parts. It is often referred to as a pie chart since it looks like a pie cut into pie-shaped pieces, or wedges. The parts of a circle graph are usually shown as percents. The entire circle graph represents 100% of the whole. To construct a circle graph, find percents of 360 ° and use a protractor to draw angles for each wedge.

Working with Circle Graphs 1) To determine the amount represented by a particular part of the graph, multiply the total amount by the percent shown in that part. 2) Change the % to a decimal and carefully multiply. 3) Check your work The total cost of a trip = $50. 30% is allocated for transportation costs. How much actual $ is allocated for transportation? 50 x.30 = $15.00 for transportation

Total cost = $1050 from 25 students 40% 30% 15% 15% How much does it cost a person if they don’t go to the show? A) 25 x C = 1050 C = 1050÷25 C = $42 per student B) 42 x 15% = 42 x 0.15 = $6.30 cost of show C) 42 – 6.30 = $37.50 for trip w/o show

Try It! 40% 30% 15% 15% How much is the cost for transportation for one student? 30% x $42 =.3 x 42 = $ ) w/o lunch or show, total cost for one student? 15% x $42 =.15 x 42 = $6.3 = 42 – ( ) = $ ) Cost of 1 admission ticket? 40% x $42 = 0.4 x 42 = $16.80

Objective Review To use circle graphs to solve problems Why? You now know how to read a type of graph often used in newspapers and magazines. When solving problems involving circle graphs, you often have to read the percent from the graph, an find the percent of that number that represents the whole.

Independent Practice Complete problems Copy original problem first. Show all work! If time, complete Mixed Review: If still more time, work on Accelerated Math.