Adding and Subtracting Fractions

Follow these steps for adding or subtracting fractions:

Example: 6/9 + 3/18

Step 1: Find a common denominator.

                    A common denominator for 9 and 18 is 18, so change 6/9
                    to 12/18 by multiplying the numerator and denominator by 2.

                   The new equation becomes :12/18 + 3/18
                                     

Step 2: Add or subtract the numerators.
                     

                   In this case, we need to add: 12 + 3 

Step 3: The denominator stays the same.

                  We get :12/18 + 3/18 = 15/18

Step 4: Put the answer in lowest terms.

                   Lowest terms :15/18 = 5/6

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