Answer:
A factor is basically a number that derives from another without leaving a remainder. It sounds somewhat confusing when put into words but I'll give you some examples.
Explanation:
in the problem you stated the answer would be yes. 3 is a factor of 372 because you can multiply 3 times another number (which in this case is 124) to get 372.
In addition, a number can have several factors. For example, these are all the factors for the number 10: 1, 2, 5, 10
notice how all these numbers multiplied by another of these same numbers on the list give you 10.
hope this helped :)