Least Common Multiple (LCM) of 81 and 20
The least common multiple (LCM) of 81 and 20 is 1620.
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 81 and 20?
First, calculate the GCD of 81 and 20 using the Euclidean algorithm. Then use the formula above to find the LCM.
Step-by-Step GCD Calculation
| Step | Calculation |
|---|---|
| 1 | 81 ÷ 20 = 4 remainder 1 |
| 2 | 20 ÷ 1 = 20 remainder 0 |
Examples of LCM Calculations
| Numbers | LCM |
|---|---|
| 185 and 22 | 4070 |
| 90 and 51 | 1530 |
| 120 and 24 | 120 |
| 197 and 169 | 33293 |
| 40 and 184 | 920 |