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Least Common Multiple (LCM) of 15 and 42

The least common multiple (LCM) of 15 and 42 is 210.

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 15 and 42?

First, calculate the GCD of 15 and 42 using the Euclidean algorithm. Then use the formula above to find the LCM.

Step-by-Step GCD Calculation

StepCalculation
1 15 ÷ 42 = 0 remainder 15
2 42 ÷ 15 = 2 remainder 12
3 15 ÷ 12 = 1 remainder 3
4 12 ÷ 3 = 4 remainder 0

Examples of LCM Calculations

NumbersLCM
173 and 18231486
154 and 18013860
60 and 18180
150 and 111650
179 and 10719153

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