Understanding Ratios and Proportions

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What is a ratio?

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A ratio is a comparison of two quantities, showing how many times one value contains or is contained within the other. For example, the ratio of 2 to 3 can be written as 2:3.

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How do you convert a decimal to a percent?

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To convert a decimal to a percent, multiply the decimal by 100 and add a percent sign. For example, 0.25 becomes 0.25 x 100 = 25%.

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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 find 10% of a number?

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To find 10% of a number, divide the number by 10. For example, 10% of 50 is 50 ÷ 10 = 5.

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What is the formula to find the original price after a discount?

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The formula to find the original price is: Original Price = Sale Price ÷ (1 - Discount Rate). For example, if the sale price is $85 and the discount is 15%, the original price is $85 ÷ (1 - 0.15) = $100.

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How do you convert a fraction to a decimal?

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What is the relationship between ratios and fractions?

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How do you scale a recipe using ratios?

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To scale a recipe, maintain the same ratio of ingredients. For example, if a recipe calls for 2 cups of sugar for every 3 cups of flour, using 6 cups of flour requires 4 cups of sugar.

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What does it mean to find a percent of a number?

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Finding a percent of a number means calculating how much that percent represents in terms of the number. For example, 25% of 200 is 0.25 x 200 = 50.

Front

How do you express 0.6 as a fraction?

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