Unit Rates & Proportions

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What is a unit rate?

Back

A unit rate is a comparison of two different quantities where one of the quantities is expressed as a quantity of one. For example, if a car travels 300 miles in 5 hours, the unit rate is 60 miles per hour.

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How do you find a unit rate from a ratio?

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To find a unit rate from a ratio, divide the first quantity by the second quantity. For example, if the ratio is 4 apples for $2, the unit rate is 4 apples ÷ 2 = 2 apples per dollar.

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What is a proportion?

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A proportion is an equation that states that two ratios are equal. For example, if a/b = c/d, then a, b, c, and d are in proportion.

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How do you solve a proportion?

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To solve a proportion, cross-multiply the terms and set the products equal to each other. For example, if a/b = c/d, then ad = bc.

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If 5 ice cream bars cost $12.25, how do you find the cost of one ice cream bar?

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To find the cost of one ice cream bar, divide the total cost by the number of bars: $12.25 ÷ 5 = $2.45.

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What is the relationship between ratios and proportions?

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Ratios compare two quantities, while proportions show that two ratios are equal. For example, if the ratio of boys to girls is 2:3, a proportion could be 2/3 = 4/6.

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How can you use proportions to solve real-world problems?

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You can use proportions to find unknown values in real-world situations, such as scaling recipes or calculating distances. For example, if a recipe for 4 servings requires 2 cups of flour, you can find how much flour is needed for 10 servings using proportions.

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What is the formula for finding a unit price?

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The formula for finding a unit price is: Unit Price = Total Price ÷ Quantity. For example, if a pack of 6 bottles costs $3, the unit price is $3 ÷ 6 = $0.50 per bottle.

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How do you maintain proportions when adjusting a recipe?

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To maintain proportions when adjusting a recipe, multiply or divide all ingredients by the same factor. For example, if a recipe calls for 2 cups of flour and you want to double it, use 4 cups of flour.

Front

What is the unit rate of 150 miles in 3 hours?

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The unit rate is 150 miles ÷ 3 hours = 50 miles per hour.