Slide 1

4.6 Percent Problems 1 Base: The number that represents the whole or 100%. Amount: The number that represents part of a whole. Percent: The number that defines what part the amount is of the whole. Percent Equation: Percent Base = Amount or P B = A Procedure: Solving Percent Problems using a Percent Equation: 1. Percents must be converted to a decimal or a fraction. 2. what percent: percent is unknown of what number: base is unknown is what number: amount is unknown 3. Substitute the values given into the percent equation. One of the values will not be given; either P, B, or A. 4. Solve the equation. If finding a percent, convert the decimal to a percent. P = percentA = AmountB = Base Example 1. 75% of what number is 60. Solution: 1. List the given information. 2. Substitute the information into the equation and solve. 0.75 B = 60 P=0.75 B=? A = 60 Equation: P B = A 0.75 B = 80 75% of 80 is 60. Answer: 90 Your Turn Problem #1 20% of what number is 18?

Slide 2

4.6 Percent Problems 2 Example 2. 105 is what percent of 140? Solution: 1. List the given information. 2. Substitute the information into the equation and solve. P 140 = 105 P=? B=140 A = 105 Equation: P B = A 140 P = 75% 105 is 75% of 140. Answer: 15% Your Turn Problem #2 81 is what percent of 540? P = 0.75 Division not shown Example 3. 14% of 28 is what number? Solution: 1. List the given information. 2. Substitute the information into the equation and solve. 0.14 28 = A P=0.14 B=28 A =? Equation: P B = A Answer: 9.01 Your Turn Problem #3 5% of 180.2 is what number? 14% of 28 is 3.92. A = 3.92 Multiplication not shown

Slide 3

4.6 Percent Problems 3 Solution: 2. List the given information. 3. Substitute the information into the equation and solve. To solve an equation with a fraction in front of the variable, multiply both sides by its reciprocal on both sides. P = 2/9 B=? A =46 Equation: P B = A B = 207 22 2/9% of 207 is 46. Answer: 174 1. P must be written as a decimal or a fraction. Your Turn Problem #4

Slide 4

4.6 Percent Problems 4 This is another method for solving percent problems. 1. The percent will not need to be converted to a decimal or a fraction (because of the 100 in the formula). Solving Percent Problems using Proportions 2. Substitute the values given in into the formula and solve the equation. Example 5. 31% of what number is 6975? Solution: 1. List the given information. 2. Substitute the information into the formula and solve. B = 22,500 Your Turn Problem #5 548 is what percent of 2740? 31 B = 697500 P = 31 B= ? A = 6975 Answer: 20% The End B.R. 6-6-08