If you have a closer look, there is no major difference between the 3 B Schools. So I have made it easier by judging them on the basis of 2 parameters only.

Admissions: Most competent students get a call from 2 of these 3 institutes as all the 3 to have similar requisites 

Placements: The placements are also at a similar level. The profiles and packages offered are similar in all the 3 B Schools except that IMT is a little behind owing to its huge batch size.

So I would say the order would be as this- XIMB >=IMI>IMT

The table below will give you a better picture of the comparison between the 3 colleges