GCF & LCM worksheets
GCF & LCM worksheets give students in Grade 4 to Grade 6 focused practice in greatest common factor and lowest common multiple. This page has 18 free printable sets, grouped by grade, and every set includes a computed answer key that is never wrong. Print them or save as a PDF, no login needed, or generate a fresh one.
What is gcf & lcm?
The greatest common factor is the largest factor two numbers share; the lowest common multiple is the smallest multiple they share.
How to teach it
List factors (for the highest common factor) or multiples (for the lowest common multiple) of each number and find the shared one. Later use prime factors.
Worked example
Common mistake
Mixing up which to list (factors vs multiples), and stopping before finding the common value.
What's inside
- Find the LCM of 3 and 9:
- Find the LCM of 2 and 11:
- Find the LCM of 11 and 7:
- Find the GCF of 11 and 12:
- Find the LCM of 9 and 4:
- Find the GCF of 9 and 8:
Sample questions. Each set (A, B, C…) has fresh numbers and a computed answer key.
Grade 4 GCF & LCM
All Grade 4 worksheets →Grade 5 GCF & LCM
All Grade 5 worksheets →Grade 6 GCF & LCM
All Grade 6 worksheets →Frequently asked questions
Are these gcf & lcm worksheets free?
Yes. Every worksheet on ChalkBee is free to view, print and download as a PDF. There is no paywall and you do not need to log in or create an account.
Do the worksheets have answer keys?
Yes. Every set comes with a full answer key. For maths, the answers are computed in code from the exact numbers printed on the sheet, so the key is never wrong.
What grades do gcf & lcm worksheets cover?
GCF & LCM worksheets on this page cover Grade 4 to Grade 6. There are 18 printable sets in total, grouped by grade so you can pick the right level.
How do I print or download them?
Open any set, then use your browser's print option to print it or to save it as a PDF. The pages are laid out to print cleanly on standard letter or A4 paper.