CAT

Even I am a commerce student who did not take up maths. The CAT Maths is just general and basic quant that you learn till 10th. You just have to apply logic and nothing else. If you will practice well you will find it really easy and you can crack the quant section for sure. It is not that difficult. All you need is self confidence and good practice.

DMS follows profile based shortlisting. So exact CAT cutoff is never declared. There is a calculation of a composite score for candidates.
The fee for 2016 batch is approximately Rs 5 lakhs including hostel. But it has been increased for 2017 batch to around Rs 9 lakhs.
The placement team published placement report on the website. You can have a look at it by visiting http://dms.iitd.ac.in/

Now, preparing for CAT isn't too difficult. If you have time issues, try online learning organised by famous teachers. These are time efficient and cost less than the normal tuition.
These are great options for you. And to improve your reading habits, just read newspaper daily. You will stay up to date with the latest information and improve your current affairs knowledge and improve reading habits too.

No, now the CAT score is not required. You just have to clear the entrance exam.

Decent chances. You may get through PGDM, MMS bleak chances.

If you don't want to take any exams then there are college based exams like DY Patil has its own exam Symbiosis has its own exam SNAP, Narsee Monjee has its own exam and on the basis of their cut-off scores, you will get admission, otherwise, there is as such no provision to get admission for any course without any entrance exam.

That is totally for you to decide. If you have specific questions for us then do ask. We will surely help you. Thank you. Have a nice day.

Yes, but you need to perform well in GD-PI too.

IIM-Bangalore has some strict percentage criteria for boards (80% above in 10th and 12th, if I am not wrong). So, B might be off the books, but you still seem to have a decent chance at C with a high percentile. I don't want to be blunt, but you will really need to nail CAT hard. Otherwise, try looking at ISB, etc. wherein the admission isn't so marks based.
Good luck.

By now you would have understood if your interest lies in engineering. In case you have any interest and you want to pursue engineering as a career then GATE is for you. In case you like management then CAT is for you. But just to let you know, at any stage of life management is necessary, hence having an MBA degree and learning from it would always benefit you irrespective of your career path.