ADDITION - Example 5

Rule 18:
To add fractions, the denominators must be equal. Complete the following steps to add two fractions.
Build each fraction so that both denominators are equal.
Add the numerators of the fractions.
The denominators will be the denominator of the built-up fractions.
Reduce the answer.

Calculate tex2html_wrap_inline52 .
The Answer is tex2html_wrap_inline54 .
The denominators are different; therefore, the first step is to build the fractions to fractions with common denominators. 15 can be factored as follows: 15 = 3 tex2html_wrap_inline56 5 and 22 can be factored as follows: 22 = 2 tex2html_wrap_inline56 11.
Rewrite both fractions where the denominators are in factored form.

tex2html_wrap_inline60 .

Multiply each fraction by the form of 1 that will yield denominators with the same set of factors. (i.e., you can find each set of factors in the denominator of the answer)


Add the numerators for the numerator in the answer.
88 + 45 = 133. The answer is tex2html_wrap_inline64 .
This answer is already reduced.

You can check the answer with your calculator. Calculate 4 divided by 15, 3 divided by 22, and add the answers. Now divide 133 by 330. Both answers should be the same.

If you are correct, the answers are the same (equivalent) and you have successfully added two fractions.

[Previous Example] [Menu Back]

S.O.S MATHematics home page

Do you need more help? Please post your question on our S.O.S. Mathematics CyberBoard.

Author:Nancy Marcus

Copyright 1999-2019 MathMedics, LLC. All rights reserved.
Contact us
Math Medics, LLC. - P.O. Box 12395 - El Paso TX 79913 - USA
users online during the last hour