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Least Common Multiple (LCM) of 72 and 21

The least common multiple (LCM) of 72 and 21 is 504.

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 72 and 21?

First, calculate the GCD of 72 and 21 using the Euclidean algorithm. Then use the formula above to find the LCM.

Step-by-Step GCD Calculation

StepCalculation
1 72 ÷ 21 = 3 remainder 9
2 21 ÷ 9 = 2 remainder 3
3 9 ÷ 3 = 3 remainder 0

Examples of LCM Calculations

NumbersLCM
88 and 922024
92 and 736716
174 and 403480
35 and 75525
185 and 501850

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