Sum formulas to the rescue!
It is a formula that the sum of the first n odd numbers is n^2. There are (203+1)/2 = 102 odd numbers here, so our numerator is 102^2.
Our denominator is 2*(1+2+3+...+102), which, by the triangular number theorem, is 102(103).
Thus, our answer is 102^2/(102*103) = 102/103