Least Common Multiple (LCM) of 138 and 21
The least common multiple (LCM) of 138 and 21 is 966.
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 138 and 21?
First, calculate the GCD of 138 and 21 using the Euclidean algorithm. Then use the formula above to find the LCM.
Step-by-Step GCD Calculation
| Step | Calculation |
|---|---|
| 1 | 138 ÷ 21 = 6 remainder 12 |
| 2 | 21 ÷ 12 = 1 remainder 9 |
| 3 | 12 ÷ 9 = 1 remainder 3 |
| 4 | 9 ÷ 3 = 3 remainder 0 |
Examples of LCM Calculations
| Numbers | LCM |
|---|---|
| 122 and 108 | 6588 |
| 160 and 131 | 20960 |
| 74 and 170 | 6290 |
| 187 and 143 | 2431 |
| 13 and 25 | 325 |