LCM( 39, 90, 60, 120 ) = 4680
Step 1 : Place the numbers inside division bar:
39 | 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 3. If any number is not divisible by 3 write it down unchanged.
3 | 39 | 90 | 60 | 120 |
13 | 30 | 20 | 40 |
Step 3 : Repeat Step 2 until you can no longer divide.
3 | 39 | 90 | 60 | 120 |
2 | 13 | 30 | 20 | 40 |
13 | 15 | 10 | 20 |
3 | 39 | 90 | 60 | 120 |
2 | 13 | 30 | 20 | 40 |
2 | 13 | 15 | 10 | 20 |
13 | 15 | 5 | 10 |
3 | 39 | 90 | 60 | 120 |
2 | 13 | 30 | 20 | 40 |
2 | 13 | 15 | 10 | 20 |
5 | 13 | 15 | 5 | 10 |
13 | 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 = 39 · 90 · 60 · 120 = 4680