45 percentile in CAT. Which colleges can I apply for?

Hey,
Well,45 percentile is too low a score for entrance examinations like CAT and you can expect nothing out of it. Even private colleges would not be accepting it. So,it would be better if you give yourself another chance. Appear for it again. Study hard and this time with more vigour.
Because CAT score plays the major role to get you a seat at good Business Schools.
Hope this helps.
Good luck.

Since your score is at the lower side I would suggest you to reappear for the CAT examination next year. With this score it is not possible to get an interview call from any of the good B Schools.
If you have appeared for other entrance tests like XAT, SNAP, CMAT etc you can use that score for your admission.
All the best