\(Q=\dfrac{8^5.\left(-5\right)^8-\left(-2\right)^5.10^9}{2^{16}.5^7+20^8}\)
\(Q=\dfrac{2^{15}.5^8+2^5.2^9.5^9}{2^{16}.5^7+4^8.5^8}\)
\(Q=\dfrac{2^{14}.5^8\left(2+5\right)}{2^{16}.5^7+2^{16}.5^8}\)
\(Q=\dfrac{2^{14}.5^8.7}{2^{16}.5^7\left(1+5\right)}\)
\(Q=\dfrac{5.7}{2^2.6}=\dfrac{35}{24}\)