Your Answer
Obviously CMAT is easier than CAT.
CAT is the top most coveted exam for a management student. The difficulty level is high compared to CMAT. If you want to take admission in IIMs you must take CAT else for admission to Tier 2 B-school you can take CMAT. Preference is always for CAT
I would like to add that
Yes it is possible to crack CMAT in 3 months. The CMAT is a three hour computer based online test which is conducted in a single session to evaluate the candidate’s ability across various segments like Quantitative Technique, Logical Reasoning, Language Comprehension and General Awareness.