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Chapter 6. Ratio, Proportion, and Percent. Ratio and Proportion. 6.1. 53% =. Writing Ratios as Fractions. A ratio is the quotient of two quantities. For example, a percent can be thought of as a ratio, since it is the quotient of a number and 100. or the ratio of 53 to 100. a. b.
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Chapter 6 Ratio, Proportion, andPercent
53% = Writing Ratios as Fractions A ratio is the quotient of two quantities. For example, a percent can be thought of as a ratio, since it is the quotient of a number and 100. or the ratio of 53 to 100
a b Ratio The ratio of a number a to a number b is their quotient. Ways of writing ratios are a to b, a : b, and
A proportion is a statement that two ratios are equal. If and are two ratios, then is a proportion. = a a c c b d b d Solving Proportions
bc ad = a c c a b b d d cross product cross product Solving Proportions A proportion contains four numbers. If any three numbers are known, the fourth number can be found by solving the proportion. To solve use cross products. Multiply both sides by the LCD, bd These are called cross products. ad= bc Simplify
Determining Whether Proportions are True ? True proportion
Finding Unknown Numbers in Proportions Cross multiply. Simplify the left side. Divide both sides by 28. Check:
Solving Problems by Writing Proportions A 16-oz Cinnamon Mocha Iced Tea at a local coffee shop has 80 calories. How many calories are there in a 28-oz Cinnamon Mocha Iced Tea? Solve the proportion. Cross multiply. Simplify the right side. Divide both side by 140. A 28-oz Cinnamon Mocha Iced Tea has 140 calories.
Helpful Hint When writing proportions to solve problems, write the proportions so that the numerators have the same unit measures and the denominators have the same unit measures. For example,