# Fraction Rules

Quick rules for adding, subtracting, multiplying, and dividing fractions.

## Addition and Subtraction Steps:

- Change all mixed numbers into improper fractions.
- Find a common denominator (least common multiple).
- Change the fractions to like fractions.
- Add or subtract the numerators.
- Keep the denominator.
- Simplify.

## Multiplication Steps:

- Change all mixed numbers into improper fractions.
- Do cancellations as many times as necessary.
- Multiply the remaining numbers across the top for the numerator and across the bottom for the denominator.

## Division Steps:

- Change all mixed numbers into improper fractions.
- Keep the first fraction.
- Change the division sign to a multiplication sign.
- Invert the second fraction.
- Follow the rules for multiplication.

(Submitted by: Cathy Pasinski; Last updated: April 5, 2013)