What is the gcm of 12 and 120?

Answer 1

There is no Greatest CommonMultiple - whatever common multiple you get, you can always add another Lowest CommonMultiple and get another, higher, common multiple.

Methinks you want either:

• Lowest CommonMultiple - the smallest number that is a multiple of both 12 and 120 which is 120; or
• Greatest CommonFactor - the largest number that divided into both 12 and 120 which is 12.