What is the relationship of two numbers a and b if their Lcm is a

Question

No other descriptions 

Answer 1

"Their LCM (Least Common Multiple) is a"  means that:

   (1) a is a multiple of a       [obviously]

   (2) a is a multiple of b       [the least common multiple of a and b]

 

This also means that "b is a factor of a."

 

For example, the LCM of a=15 and b=5 is a=15.

    15 is a multiple of 15

    15 is a multiple of 5

  5 is a factor of 15.

Answer 2

b is a multiple of a.