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Prime Factors, HCF and LCM

Lowest Common Multiple (LCM)

The least common multiple of any two numbers a and b, denoted by LCM(a,b), is the smallest number that is divisible by both a and b.

To find the LCM of two numbers:

• Express each number as a product of prime powers.
• For each prime factor choose the prime power with largest exponent among all numbers.
• The LCM is the product of the chosen prime powers.

Example

Click on the question marks to see the example step by step.

Exercise

Find the lowest common multiple (LCM) of the pairs of numbers.

Another method for obtaining the LCM, is to find the HCF then

Example

<< Highest Common Factor | HCF andLCM Index |