JEE

Hello,
If your study for 4 hours and understand the logic and concept instead of studying for 10 hours just "solving problems" the former will yield definitely more marks than the later.
As maths is almost every time easy (if you have interest) in JEE comparing to others. So, I suggest in order to cover it in a limited time frame follow these steps.
Every day before starting draw out a rough plan of what topics you will cover today pointwise.
Then start working on it and as I said before whatever you do understand the logic of it and only then do it else leave it because it will be a waste of time otherwise. Once you are 100% sure you have understood the topic solve its primitive examples.
Then pick 10 problems related to the same topic and all should be of different type and varying difficulty. Solve those 10 problems and then look at your rough plan and jump to the next topic. In between do take breaks or else you will get bored soon and scrap the whole plan.
All the best!