Rule 19: SUBTRACTION

To subtract, the denominators must be equal. You essentially following the same steps as in addition.

1.
Build each fraction so that both denominators are equal.
2.
Combine the numerators according to the operation of subtraction or additions.
3.
The denominators will be the denominator of the built-up fractions.
4.
Reduce the answer.

Example:
Calculate tex2html_wrap_inline48 .

Answer:
The answer is tex2html_wrap_inline50 .

Solution:
The denominators are the same, so you can skip step 1. The denominator of the answer will be 5. Combine the numerators for the numerator in the answer. 3 - 1 = 2. The answer is tex2html_wrap_inline54 . This answer is already reduced, so you can skip step 4.

Check:
You can check the answer with your calculator. Calculate 3 divided by 5, calculate 1 divided by 5, and subtract the second answer from the first. Now divide 2 by 5. Both answers should be the same. If you are correct, the answers are the same (equivalent) and you have successfully combined two fractions with the operation of subtraction.

If you would like to review another example, click on the word Example.

Work the following problems and click on Answer to check your results.

Problem 1:
Calculate tex2html_wrap_inline56 and reduce your answer. Answer

Problem 2:
Calculate tex2html_wrap_inline58 and reduce your answer. Answer

Problem 3:
Add the fractions tex2html_wrap_inline60 and reduce your answer. Answer

Problem 4:
Add the fractions tex2html_wrap_inline62 and reduce your answer. Answer

Problem 5:
Add the fractions tex2html_wrap_inline64 and reduce your answer. Answer

Back to Simple Fractions

[Identification] [Factoring Integers] [Reducing Fractions] [Multiplication]
[Division] [Building Fractions] [Addition] [Subtraction]
[Order of Operation]

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Author:Nancy Marcus

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