Question 991477
5^-2 / 4^6 = (1/5^2) / (4^6) = (1/5^2) * (1/4^6) = 1 / (5^2 * 4^6).


i believe that's as simple as it gets without actually evaluating 5^2 = 25 and 4^2 = 4096 and then multiplying 25 * 4096 to get 1/102400.