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Least Common Multiple (LCM) of 42 and 80

The least common multiple (LCM) of 42 and 80 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 42 and 80?

First, calculate the GCD of 42 and 80 using the Euclidean algorithm. Then use the formula above to find the LCM.

Step-by-Step GCD Calculation

StepCalculation
1 42 ÷ 80 = 0 remainder 42
2 80 ÷ 42 = 1 remainder 38
3 42 ÷ 38 = 1 remainder 4
4 38 ÷ 4 = 9 remainder 2
5 4 ÷ 2 = 2 remainder 0

Examples of LCM Calculations

NumbersLCM
126 and 1382898
162 and 10810
47 and 1296063
145 and 19327985
138 and 632898

Try Calculating LCM of Other Numbers







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