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Chapter 6 Lesson 5 Using the Percent Proportion pgs. 288-292. What you will learn: Use the percent proportion to solve problems. Vocabulary. Part (288): numerator Base (288): denominator Percent Proportion (288): comparing a percent, written as a fraction , whose base is 100 to a proportion
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Chapter 6 Lesson 5Using the Percent Proportionpgs. 288-292 What you will learn: Use the percent proportion to solve problems
Vocabulary Part (288): numerator Base (288): denominator Percent Proportion (288): comparing a percent, written as a fraction , whose base is 100 to a proportion part <----- 3 = 75 -------> part base <----- 4 100 ------> base
Key Concept (288)Percent Proportion • Words: part = percent base 100 Symbols: a = p , where a is the part, b 100 b is the base and p is the percent.
Example 1: Find the Percent Seventy-two is what percent of 160? Seventy-two is being compared to 160. So, 72 is the part and 160 is the base. Let p represent the percent. a = P ----> 72 = P b 100 160 100 Find the cross products: 72100 = 160P Simplify: 7200=160P Divide: 7200 = 160P 160 160 Solve: 45 = P So, 72 is 45% of 160
Example 2: Find the Percent • What percent of 5 is 8? Eight is being compared to 5. So 8 is the part and 5 is the base. Let P represent the percent. a = P ----> 8 = P b 100 5 100 Cross Products: 8100 =5P Simplify: 800=5P Divide: 800 = 5P 5 5 Solve: 160 = P So, 160% of 5 is 8
Example 3: Apply the Percent Proportion • If 12 of the 75 animals in a pet store are parakeets, what percent are parakeets? a = P = 12= P b 100 75 100 Cross Products: 12100 = 75P Simplify: 1200 = 75P Divide: 1200 = 75P 75 75 Solve: 16 = P So, 16% of the animals are Parakeets
Example 4: Find the Part • What number is 3.5% of 750? The percent is 3.5 and the base is 750. Let a represent the part. a = P ------> a = 3.5 b 100 750 100 Cross Products: a100 = 7503.5 Simplify: 100a = 2625 Divide: 100a = 2625 100 100 Solve: a = 26.25 So, 3.5% of 750 is 26.25
Example 5: Apply the Percent Proportion • Of the fish in an aquarium, 26% are angelfish. If the aquarium contains 50 fish, how many are angelfish? • To find 26% of 50, let b represent the base, 50, and let p represent the percent 26% in the percent proportion. Let a represent the part. a = P ---> a =26 b 100 50 100 a100 = 5026 100a = 1300 a = 13 So, 13 fish are angelfish
Example 6: Find the Base • 27 is 90% of what number? The percent is 90% and the part is 27. Let b represent the base. a = P ----> 27 = 90 b 100b 100 Cross Products: 27100 = b90 Simplify: 2700 = 90b Divide: 2700 = 90b 90 90 Solve: 30= b So, 27 is 90% of 30
Your Turn! Use the percent proportion to solve each problem, round to the nearest tenth. 17 = P 100 P = 20 20% 17 is what percent of 85? 36 is 72% of what number? What is 84% of 150? What is 0.3% of 750? 36 = 72 b 100 b = 50 a = 84 100 a = 126 a = 0.3 100 a = 2.25
Make sure you carefully Read & understand what The question is asking! Extra Practice by the door! Quiz Tomorrow! (6-4 & 6-5)