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.

Example:
Calculate .
Solution:
The denominators are different, so you must build each fraction to a form where they both have the same denominator. Since both 2 and 3 will divide evenly into 6, build both fractions to a denominator of 6. and .
can now be written .
3 + 1 = 4. The answer is .

Check:
You can check the answer with your calculator. Calculate 1 divided by 2, calculate 1 divided by 3, and add the results. Now divide 5 by 6. 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