What is less common factor LCF?

Answer 1

The lowest common factor between two numbers is the multiple apart from 1 that the two numbers share which is the lowest.

For example: The numbers 36 and 45.

Multiples of 36 are {1,2,3,4,6,9,12,24,36}

Multiples of 45 are {1,3,5,9,15,45}

It is evident that their shared multiples are 1,3,9. But we exclude 1, therefore 3 is the LCM (or LCF)