A complacent student, who is doing his 10th standard, thinks if he gets 45 marks then it is enough. He needs to do Fire Mudra (to get better results).
To gain weight
One should do the Pran Mudra. Do it by touching your ring and little fingers with the tip of the thumb on both the hands.
To have desired results, one has to practice this Mudra at least for half an hour. You can also practice this Mudra while walking or sitting.