Do I need separate coaching for CAT and GMAT or CAT is enough?????

The CAT (Common Admission Test) is considered tough then the GMAT, so I would suggest you to take the CAT coaching it will be enough for you. The pattern for the two exams is almost the same so you need not to take different coaching for two

For your reference here I am telling you the names of some good CAT coaching centers:

Abhyaas

Ascent Education

Bulls Eye Knowledge Systems

Career Forum

Career Launcher

Emphatic Result Academy

Endeavor

ERUDITE

Foundation Studies for Management

PRIME Tutor

SharpMinds

T.I.M.E.

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