#### Transcript of Adding and Subtracting Fractions

**Adding and Subtracting Fractions**

**By Joe, Abigail, Lauren **

and Andee

Adding Positive Fractions

Adding Fractions

1. Find the smallest multiple (LCM) of both numbers.

2. Rewrite the fractions as equivalent fractions with the L.C.M as the denominator.

Example:

3/4+1/6= 9/12+2/12= 11/12

Subtracting Negative Fractions

Subtracting Positive Fractions

Find the least common denominator of the two fractions.

Multiply the numerator by the number you used to find the least common denominator. ex: 3/4 - 2/8

Both denominators should become 8

Since 4 * 2 = 8 You will multiply 3 * 2 which equals 6

Do the same with the second fraction

Now just subtract the two numerators, and borrow if needed.

Simplify if needed

Ex: 4 1/6 - 3 2/3

1. Change it to 3 1/6 - 3 4/6

2. In this example you need to borrow, to borrow you take one whole number from the number in front of the fraction. 3 1/6 becomes 3 7/6.

3. Now just subtract: 3 7/6 - 3 1/6 = 6/6

4. Simplify if needed: 6/6 = 1

If The problem you have does not require borrowing then just skip that step.

Adding Negative Fractions

Adding negative fractions is the same as adding positive fractions.

01. Change the second fraction into a positive number

02. Rewrite the mixed number as an improper fraction

03. Write the sum of the numerators over the common denominator and add

04. Write the improper fraction as a mixed number

Example:

-4 ¹/₇ - (-⁶/₇) = ?

-4 ¹/₇ - ⁶/₇

-²⁹/₇ - ⁶/₇

-²⁹+⁶ / 7

-²³/₇ = -3 ²/₇

Ex: -5/10+ -5/10= -1

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