A good thing about WBJEE is that questions are asked of each and every topic, unlike JEE Mains where they might decide to neglect one portion.
It's very important for you to score 40+ in mathematics to get a total of 100+.Start off with the two marks questions as one mark and two marks questions asked in WBJEE are equally difficult and lengthy.If you have a good grasp of calculus and coordinate geometry you should be able to achieve this score.Vectors and 3D geometry are the most important topics in algebra part so prepare them well.
The next section would be physics.Just like maths, questions are asked of each and every topic.You need to score a minimum 30 in this section.Mechanics, optics, modern physics, electrostatics should be enough to achieve this score, given that you are able to solve 80% of these sections.
For Chemistry, Organic and Physical(which most students find relatively easier to study) should get you around 35 marks/50, if you are able to solve all question correctly. Also, keep in mind all the exceptions in organic chemistry as in WBJEE a lot of these questions are asked.
Practice previous years IIT papers, don't solve the recent ones.A lot of relatively easier JEE(the ones that can be solved by an average Joe) questions get repeated in WBJEE, this would help you a lot.
All the very best and good luck.
If you want to get under 100 rank i am sure you are targeting to join Jadhavpur University so for that you will have to score above 170 marks in wbjee examination.
I hope this helps.
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