GCF and LCM Calculator
Greatest common factor and least common multiple of two numbers.
What is a GCF and LCM calculator?
A GCF and LCM calculator finds the greatest common factor and the least common multiple of two numbers. Example: for 12 and 18, GCF = 6 and LCM = 36.
How to use it
Enter two numbers, then tap Calculate.
Formula
The GCF is the largest number that divides both numbers. The LCM is found from the GCF: LCM = (first number × second number) ÷ GCF.
Example
Factors of 12: 1, 2, 3, 4, 6, 12. Factors of 18: 1, 2, 3, 6, 9, 18. Common factors: 1, 2, 3, 6. The greatest is 6, so GCF = 6. LCM = 12 × 18 ÷ 6 = 36.
Frequently Asked Questions
What is the GCF of 12 and 18?
6.
What is the LCM of 12 and 18?
36.
How is the LCM found from the GCF?
LCM = (first number × second number) ÷ GCF.
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