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Least Common Multiple (LCM) of 42 and 84

The least common multiple (LCM) of 42 and 84 is 84.

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 42 and 84?

First, calculate the GCD of 42 and 84 using the Euclidean algorithm. Then use the formula above to find the LCM.

Step-by-Step GCD Calculation

StepCalculation
1 42 ÷ 84 = 0 remainder 42
2 84 ÷ 42 = 2 remainder 0

Examples of LCM Calculations

NumbersLCM
121 and 12214762
140 and 18325620
192 and 902880
47 and 251175
48 and 38912

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