Will they give a paper to work out mathematics

Hello Sundhar,
You didn't specify the exam you are talking about but fo your information, in each and every exam, which includes mathematics and where the calculations are required, they provide papers for calculation. Some exams do allow calculator to carry in the exam for calculations.
If any paper or calculator is not being provided, you will definitely have some options to do calculations, whether it can be the question paper or any other thing.
So you don't need to worry about it, just prepare well.
All the best.