7 5 Percents Learn to write percents as

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7 -5 Percents Learn to write percents as decimals and as fractions.

7 -5 Percents Learn to write percents as decimals and as fractions.

7 -5 Percents Vocabulary percent

7 -5 Percents Vocabulary percent

7 -5 Percents Most states charge sales tax on items you purchase. Sales tax

7 -5 Percents Most states charge sales tax on items you purchase. Sales tax is a percent of the item’s price. A percent is a ratio of a number to 100. You can remember that percent means “per hundred. ” For example, 8% means “ 8 per hundred, ” or “ 8 out of 100. ”

7 -5 Percents If a sales tax rate is 8%, the following statements are

7 -5 Percents If a sales tax rate is 8%, the following statements are true: • For every $1. 00 you spend, you pay $0. 08 in sales tax. • For every $10. 00 you spend, you pay $0. 80 in sales tax. • For every $100 you spend, you pay $8 in sales tax. Because percent means “per hundred, ” 100% means “ 100 out of 100. ” This is why 100% is often used to mean “all” or “the whole thing. ”

7 -5 Percents Additional Example 1: Modeling Percent Use a 10 -by-10 -square grid

7 -5 Percents Additional Example 1: Modeling Percent Use a 10 -by-10 -square grid to model 17%. A 10 -by-10 square grid has 100 squares. 17% means “ 17 out of 100” 17 ___ or. 100 Shade 17 squares out of 100 squares.

7 -5 Percents Check It Out: Example 1 Use a 10 -by-10 -square grid

7 -5 Percents Check It Out: Example 1 Use a 10 -by-10 -square grid to model 26%. A 10 -by-10 square grid has 100 squares. 26% means “ 26 out of 100” 26 ___ or. 100 Shade 26 squares out of 100 squares.

7 -5 Percents Additional Example 2: Writing Percents as Fractions Write 35% as a

7 -5 Percents Additional Example 2: Writing Percents as Fractions Write 35% as a fraction in simplest form. 35 Write the percent as a fraction with 35% = ___ 100 a denominator of 100. 35 ÷ 5 = __ 7 _______ 100 ÷ 5 20 Write the fraction in simplest form. 7 Written as a fraction, 35% is __. 20

7 -5 Percents Check It Out: Example 2 Write 65% as a fraction in

7 -5 Percents Check It Out: Example 2 Write 65% as a fraction in simplest form. 65 Write the percent as a fraction with 65% = ___ 100 a denominator of 100. 65 ÷ 5 = 13 _______ __ 100 ÷ 5 20 Write the fraction in simplest form. 13 Written as a fraction, 65% is __. 20

7 -5 Percents Additional Example 3: Life Science Application Janell has 20% body fat.

7 -5 Percents Additional Example 3: Life Science Application Janell has 20% body fat. Write 20% as a fraction in simplest form. 20 Write the percent as a fraction with 20% = ___ 100 a denominator of 100. 20 ÷ 20 = __ 1 _______ 100 ÷ 20 5 Write the fraction in simplest form. 1 Written as a fraction, 20% is __. 5

7 -5 Percents Check It Out: Example 3 Timmy has 14% body fat. Write

7 -5 Percents Check It Out: Example 3 Timmy has 14% body fat. Write 14% as a fraction in simplest form. 14 Write the percent as a fraction with 14% = ___ 100 a denominator of 100. 14 ÷ 2 = __ 7 _______ 100 ÷ 2 50 Write the fraction in simplest form. 7 Written as a fraction, 14% is __. 50

7 -5 Percents Additional Example 4: Writing Percents as Decimals Write 56% as a

7 -5 Percents Additional Example 4: Writing Percents as Decimals Write 56% as a decimal. 56 Write the percent as a fraction with 56% = ___ 100 a denominator of 100. 0. 56 100 56. 00 – 500 600 – 600 0 Write the fraction as a decimal. Written as a decimal, 56% is 0. 56. Remember! To divide by 100, move the decimal point two places to the left. 56 ÷ 100 = 0. 56

7 -5 Percents Check It Out: Example 4 Write 32% as a decimal. 32

7 -5 Percents Check It Out: Example 4 Write 32% as a decimal. 32 Write the percent as a fraction with 32% = ___ 100 a denominator of 100. 0. 32 100 32. 00 – 300 200 – 200 0 Write the fraction as a decimal. Written as a decimal, 32% is 0. 32.

7 -5 Percents Additional Example 5: Application Water made up 85% of the fluids

7 -5 Percents Additional Example 5: Application Water made up 85% of the fluids that Kirk drank yesterday. Write 85% as a decimal. 85 Write the percent as a fraction with 85% = ___ 100 a denominator of 100. 85 ÷ 100 = 0. 85 Write the fraction as a decimal. Written as a decimal, 85% is 0. 85.

7 -5 Percents Check It Out: Example 5 Water made up 95% of the

7 -5 Percents Check It Out: Example 5 Water made up 95% of the fluids that Lisa drank yesterday. Write 95% as a decimal. 95 Write the percent as a fraction with 95% = ___ 100 a denominator of 100. 95 ÷ 100 = 0. 95 Write the fraction as a decimal. Written as a decimal, 95% is 0. 95.