By comparing its multiples to another set of multiples.
You need at least two numbers to find an LCM.
Multiply them together. The LCM is 120.
The LCM is 40.
You need at least two numbers to find an LCM. If that's 8 and 10, the LCM is 40.
The LCM of 4, 5, and 8 is 40.
You need at least two numbers to find an LCM. If that's 5 and 40, the LCM is 40.
The LCM is 40.
You need at least two numbers to find an LCM. If that's 30 and 40, the LCM is 120.
Since 40 is a multiple of 2, it is automatically the LCM.
LCM for 10 and 40 is 40.
LCM for 5 and 40 is 40.
Since 40 is a multiple of 1, it is automatically the LCM.