ADDITION: Problem 3

Rule 18:

To add fractions, the denominators must be equal. Complete the following steps to add two fractions.

1.: Build each fraction so that both denominators are equal.
2.: Add the numerators of the fractions.
3.: The denominators will be the denominator of the built-up fractions.
4.: Reduce the answer.

Problem 3:

Add the fractions tex2html_wrap_inline60

and reduce your answer.

Answer:

The answer is

Solution:

The denominators are different, so you must build each fraction to a form where they both have the same denominator. Rewrite the problem with both denominators factored.
tex2html_wrap_inline64

The common denominator will have to have factors 2, 5, and 7. Build each fraction so that each denominators has these three factors.

tex2html_wrap_inline66 and tex2html_wrap_inline68 .

The problem tex2html_wrap_inline60 can now be written in the equivalent form tex2html_wrap_inline72 .

Reduce the answer.
tex2html_wrap_inline74 .

Check:

Now prove to yourself with your calculator that your answer is correct. Calculate 7 divided by 10, 3 divided by 14, and add the results. Now divide 32 by 35. Both answers should be the same. If you are correct, the answers are the same (equivalent) and you have successfully added two fractions.

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Author:Nancy Marcus