OML Search

Least Common Multiple or Least Common Denominator

Objective: I can find the least common multiple or least common denominator.



One way to find the least common multiple (LCM) is

Step 1: List the multiples of the two numbers.

Step 2: Find the multiples common to both numbers.

Step 3: Select the smallest common multiple.


Read the lesson on least common multiple if you need to learn how to find the lowest common multiple.


We use the least common multiple when adding or subtracting fractions with unlike denominators. It is then called the least common denominator.


Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button to get a clue. Note that you will lose points if you ask for hints or clues!
Find the LCM of the following:

6, 9

8, 12

6, 20

12, 15

15, 18

18, 27

9, 15

8, 10

12, 18

9, 12





Try the free Mathway calculator and problem solver below to practice various math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.
Mathway Calculator Widget

We hope that the free math worksheets have been helpful. We encourage parents and teachers to select the topics according to the needs of the child. For more difficult questions, the child may be encouraged to work out the problem on a piece of paper before entering the solution. We hope that the kids will also love the fun stuff and puzzles.


OML Search


We welcome your feedback, comments and questions about this site or page. Please submit your feedback or enquiries via our Feedback page.