\(\dfrac{75^{50}.2^{100}}{100^{50}.9^{25}}\)
\(=\dfrac{\left(3.5^2\right)^{50}.\left(2^2\right)^{50}}{\left(2^2.5^2\right)+\left(3^2\right)^{50}}\)
\(=\dfrac{ \left(3.25\right)^{50}.4^{50}}{\left(4.25\right)^{50}.3^{50}}\)
\(=\dfrac{3^{50}.25^{50}.4^{50}}{4^{50}.25^{50}.3^{50}}=1\)