Least Common Multiple (LCM) of 21 and 18
The least common multiple (LCM) of 21 and 18 is 126.
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 21 and 18?
First, calculate the GCD of 21 and 18 using the Euclidean algorithm. Then use the formula above to find the LCM.
Step-by-Step GCD Calculation
| Step | Calculation |
|---|---|
| 1 | 21 ÷ 18 = 1 remainder 3 |
| 2 | 18 ÷ 3 = 6 remainder 0 |
Examples of LCM Calculations
| Numbers | LCM |
|---|---|
| 175 and 198 | 34650 |
| 188 and 41 | 7708 |
| 118 and 69 | 8142 |
| 181 and 163 | 29503 |
| 71 and 159 | 11289 |