Hi Swati,
It is true that you need a lot of practice to ace subjects like Maths.
Don't be disheartened by the lack of questions in your school textbook. WBBSE's mathematics curriculum is comparable to CBSE's mathematics curriculum.
Therefore, after solving the 10 - 20 questions of your school textbook, you can opt for standard maths textbook such as the ones by authors like R.D Sharma and R.S Agarwal. These books contain hundreds of questions on each topic and will provide you ample opportunities to hone your knowledge.
Books for class 11th:
1. Senior Secondary School Mathematics for Class 11 by RS Agarwal (paperback costs rupees 600 on Amazon).
2. Mathematics for class 11 by RD Sharma (paperback costs about rupees 645 on Amazon).
I hope this information helps you!
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