$${W = \frac{N!}{n_1! n_2!} = \frac{100!}{50! 50!} \\ = \frac{9,33 \times 10^{157}}{(3,04 \times 10^{64})(3,04 \times 10^{64})} \\ = \underline{\underline{1,01 \times 10^{29}}}}$$