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Subtracting Fractions

There are 3 simple steps to subtract fractions

Step 1. Make sure the bottom numbers (the denominators) are the same

Step 2. Subtract the top numbers (the numerators). Put the answer over the the same denominator as in step 1

Step 3. Simplify the fraction.

 

Example 1:

3 1
4 4

Step 1. The bottom numbers are already the same. Go straight to step 2.

Step 2. Subtract the top numbers and put the answer over the same denominator:

3  –  1  =  3 – 1  =  2
4 4 4 4

Step 3. Simplify the fraction:
2 = 1
4 2

(If you are unsure of the last step see the equivalent fractions page.)

 

Example 2:

1  –  1
2 10

Step 1. The bottom numbers are different. We need to make them the same.

We can multiply the top and bottom of ½ by 5 like this:

1  =  5
2 10

And now the bottom numbers (the denominators) are the same:

5  –  1
10 10

Step 2. Subtract the top numbers and put the answer over the same denominator:

5  –  1 = 5 – 1 = 4
10 10 10 10

Step 3. Simplify the fraction:

4  =  2
10 5

Making the Denominators the Same

In the previous example it was easy to make the denominators the same, but it can be harder ... so you may need to use either the

They both work, use whichever you prefer!


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