1. List multiples of both numbers. Start by listing four multiples for each number
2. Look at the lists you’ve made. Underline any numbers that are on both lists.
3. Look for the smallest underlined number (known as the least common multiple, or LCM). This is your common denominator.
4. Multiply the numerator and denominator by the factor that it would take to get to your common denominator.
You then add subtract multiply or divide your #'s
