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Least Common Multiple (LCM) of 120 and 42

The least common multiple (LCM) of 120 and 42 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 42?

First, calculate the GCD of 120 and 42 using the Euclidean algorithm. Then use the formula above to find the LCM.

Step-by-Step GCD Calculation

StepCalculation
1 120 ÷ 42 = 2 remainder 36
2 42 ÷ 36 = 1 remainder 6
3 36 ÷ 6 = 6 remainder 0

Examples of LCM Calculations

NumbersLCM
118 and 15718526
104 and 10711128
181 and 122172
33 and 1254125
40 and 1161160

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