On-spot Mathematics Olympiad

How many times can you subtract 7 from 83, and what is left afterwards? You can subtract it as many times as you want, and it leaves 76 every time.

Mathematicians need not be boring or orthodox. So do you dare to think mathematics in an unconventional way? Do you have an innate desire to do with numbers what artists do with paint brushes? Or can you see music in equations? So get out your pen and paper because here at Kshitij we offer you a chance to give your brains the free reign that it deserves. So pit yourself against the toughest opponents in a battle to solve the trickiest questions the fastest. Sounds difficult?? Well that depends on how large your value of '0' is...