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Least Common Multiple (LCM) of 120 and 21

The least common multiple (LCM) of 120 and 21 is 840.

What is the Least Common Multiple (LCM)?

The LCM of two integers is the smallest positive integer that is divisible by both numbers. It is often used to find common denominators and solve problems involving periodic events.

Formula for LCM

The LCM of two numbers can be calculated using their GCD:

LCM(a, b) = |a × b| ÷ GCD(a, b)

How to Calculate the LCM of 120 and 21?

First, calculate the GCD of 120 and 21 using the Euclidean algorithm. Then use the formula above to find the LCM.

Step-by-Step GCD Calculation

StepCalculation
1 120 ÷ 21 = 5 remainder 15
2 21 ÷ 15 = 1 remainder 6
3 15 ÷ 6 = 2 remainder 3
4 6 ÷ 3 = 2 remainder 0

Examples of LCM Calculations

NumbersLCM
191 and 19537245
123 and 1777257
145 and 19828710
88 and 11910472
13 and 1992587

Try Calculating LCM of Other Numbers







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