How do you know if the question asks you to see if M is a factor of N or N is a factor of M? or m/n or n/m ?the simple logic here is both n and m must be integers..st.2 says 13*n/m is possible as 13 is a prime n/m must be an integer thus it is possible to arrange n students to m classrooms.Has to be BI came across this explanation at =>http://bt.www.beatthegmat.com/gmat-12th ... tml#331474We first