1. Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Chapter 5 Percents

2. Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. 5.6 Applications of Percent

3. Martin-Gay, Developmental Mathematics, 2e 33 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Example percent baseamount 18% of 3680 is what number? 18% of Frank’s wages are withheld for income tax. Find the amount withheld from Frank’s wages of $3680 per month. Thus, $662.40 were held from Frank’s wages.

4. Martin-Gay, Developmental Mathematics, 2e 44 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Example Mr. Buccaran, the principal of Slidell High School, counted 31 freshmen absent during a particular day. If this is 4% of the total number of freshmen, how many freshmen are there at Slidell High School? 31 is 4% of what number? Now we solve for n. 31 = 4% · n 31 = 0.04 · n There are 775 freshmen in the school. Method 1 continued

5. Martin-Gay, Developmental Mathematics, 2e 55 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. continued Mr. Buccaran, the principal of Slidell High School, counted 31 freshmen absent during a particular day. If this is 4% of the total number of freshmen, how many freshmen are there at Slidell High School? 31 is 4% of what number? There are 775 freshmen in the school. Method 2 amountpercent base

6. Martin-Gay, Developmental Mathematics, 2e 66 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Finding Percent of Increase Percent of Increase Then write the quotient as a percent.

7. Martin-Gay, Developmental Mathematics, 2e 77 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Example First we find the amount of increase; 19.9 – 13.1 = 6.8. The average soft-drink size has increased from 13.1 oz to 19.9 oz over the past two decades. Find the percent increase. (Source: University of North Carolina at Chapel Hill, Journal for American Medicine) The amount of increase is 6.8. To find the percent of increase,

8. Martin-Gay, Developmental Mathematics, 2e 88 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Finding Percent of Decrease Percent of Decrease Then write the quotient as a percent.

9. Martin-Gay, Developmental Mathematics, 2e 99 Copyright © 2011 Pearson Education, Inc. Publishing as Prentice Hall. Example First we find the amount of decrease; 3250 – 2100 = 1150. The amount of decrease is 1150. To find the percent of decrease, John Smith decided to decrease the number of calories in his diet from 3250 to 2100. Find the percent decrease.