See there are quite a number of factors which can go for the motion or against the motion. You yourself know how is your knowledge till now, how much you can study in a day, which is your strength and weakness, What is your efficiency rate etc. Now this are the factors dependent. I would say give your best this 90 days and see what happens. If you give your 100% then you can surely do 150 marks provided you satisfy all the factors.

I hope this helps. All the very best for your future endeavors!