LCM( 30, 90, 60, 120 ) = 360
Step 1 : Place the numbers inside division bar:
30 | 90 | 60 | 120 |
Step 2 : Find a prime number which can divide at least two of your numbers.
In this example we can divide by 2. If any number is not divisible by 2 write it down unchanged.
2 | 30 | 90 | 60 | 120 |
15 | 45 | 30 | 60 |
Step 3 : Repeat Step 2 until you can no longer divide.
2 | 30 | 90 | 60 | 120 |
2 | 15 | 45 | 30 | 60 |
15 | 45 | 15 | 30 |
2 | 30 | 90 | 60 | 120 |
2 | 15 | 45 | 30 | 60 |
3 | 15 | 45 | 15 | 30 |
5 | 15 | 5 | 10 |
2 | 30 | 90 | 60 | 120 |
2 | 15 | 45 | 30 | 60 |
3 | 15 | 45 | 15 | 30 |
5 | 5 | 15 | 5 | 10 |
1 | 3 | 1 | 2 |
Since there are no primes that divides at least two of given numbers, we conclude that the LCM is a product of starting numbers.
LCM = 30 · 90 · 60 · 120 = 360