To decrease a quantity using a ratio, you multiply the original quantity by a fraction representing the desired decreased ratio. This fraction will always be less than one.
Here's a breakdown:
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Understanding Ratios for Decrease: When you want to decrease something using a ratio, you're essentially finding a smaller proportion of the original amount. This proportion is expressed as a fraction.
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Creating the Decreasing Fraction: The ratio represents the relationship between the new, smaller quantity and the original quantity. For instance, if you want to reduce something in the ratio of 2:5, it means the new quantity will be 2 parts for every 5 parts of the original. The fraction you would use to decrease is 2/5.
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The Calculation: Multiply the original quantity by the fraction you created from the ratio. This gives you the new, decreased quantity.
Example:
Let's say you have 100 apples, and you want to decrease the number of apples in the ratio of 3:5.
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Identify the ratio: 3:5. This means you want to have 3 apples for every 5 you originally had.
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Form the fraction: 3/5.
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Multiply: 100 apples * (3/5) = 60 apples.
So, decreasing 100 apples in the ratio of 3:5 results in 60 apples.
Why this works: Multiplying by a fraction less than 1 always results in a smaller value than the original number. The fraction directly scales down the original quantity according to the given ratio.
In Summary: To decrease using ratios, create a fraction from the given ratio that represents the desired decrease and then multiply the original value by this fraction.
