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Least Common Multiple (LCM) of 80 and 21

The least common multiple (LCM) of 80 and 21 is 1680.

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 80 and 21?

First, calculate the GCD of 80 and 21 using the Euclidean algorithm. Then use the formula above to find the LCM.

Step-by-Step GCD Calculation

StepCalculation
1 80 ÷ 21 = 3 remainder 17
2 21 ÷ 17 = 1 remainder 4
3 17 ÷ 4 = 4 remainder 1
4 4 ÷ 1 = 4 remainder 0

Examples of LCM Calculations

NumbersLCM
98 and 191862
55 and 1417755
62 and 1116882
91 and 15213832
60 and 140420

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