1. Subtracting Fractions
By, Mrs. Muller

2. What does it mean to subtract Fractions?
It is when we take away a part of a whole from another part of a whole.
For example: You have 5 out of 6 slices of pie in the fridge. Your brother and you each have one slice of pie (2 out of 6 slices total). How much pie do you have left?
What do you
notice about
subtracting
fractions?

3. The Procedure The denominators must be the same
Subtract the numerators from each other.
Keep the denominators the same.

4. Let’s Practice

5. What do we do when the denominator is different?
Let’s say we have the problem ½-1/3=
Let’s use the fraction strips to come up with a rule.
What fraction strips can be used to make the ½ and the 1/3?
What do you notice about subtracting fractions with different denominators?

6. The Procedure for subtracting fractions with different denominators.
½-1/3=
First find the least common multiple of the denominators.
Second multiply the numerator by what it took to get the LCM and make the denominator the LCM
Third use the new fractions to add them together now that the denominators are the same.
2x1
2x2
2x3
3x1
3x2

7. Let’s Practice

8. Compare and Contrast Adding and Subtracting Fractions
Use a double bubble map to compare and contrast Adding and Subtracting Fractions.