a) `\frac{2^{10}.9^{41}.25^{23}}{3^{50}.15^{35}.10^9}`
=`\frac{2^{10}.(3^2)^{41}.(5^2)^{23}}{3^{50}.(3.5)^{35}.(2.5)^9}`
=`\frac{2^{10}.3^{41.2}.5^{23.2}}{3^{50}.3^{35}.5^{35}.2^9 .5^9`
=`\frac{2^{10}.3^{82}.5^{46}}{3^{50+35}.5^{35+9}.2^9}`
=`\frac{2^{10}.3^{82}.5^{46}}{3^{85}.5^{44}.2^9}`
=$\frac{2^1 . 5^2}{3^3}$
=$\frac{50}{27}$
b) $\frac{20^{16}.10^9 .35^6}{8^{12}.25^{14}.14^5}$
=$\frac{2^{16}.2^{16}.5^{16}.2^9.5^9.5^6.7^6}{2^{12}.2^{12}.2^{12}.5^{14}.5^{14}.2^5.7^5}$
=`875`