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How to subtract mixed numbers with unlike denominators?.

User Vesmy
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1 Answer

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To subtract mixed numbers with different denominators, follow these steps:

1. Rename the fractions using a common denominator.

2. Subtract whole numbers from whole numbers. You might need to regroup first.

3. Subtract fractions from fractions.

4. Simplify, if needed.

Let's try it with
2(3)/(5)-1(1)/(4)

First, rename the fractions using a common denominator. The least common denominator of these fractions is 20. Multiply to make equivalent fractions with 20 as the denominator.


(3x4)/(5x4)=(12)/(20)
(1x5)/(4x5)=(5)/(20)

Rewrite the problem and subtract the whole numbers.


2(12)/(20)-1(5)/(20)=1(?)/(?)

Now, subtract the fractions. Subtract the numerators and keep the denominator the same.


2(12)/(20)-1(5)/(20)=1(7)/(20)

This answer is already in its simplest form, so there is no need to simplify it.

User Leeks And Leaks
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