5^20 : (5^15.6 + 5^15.19)
=5^20 : [5^15.(6+19)]
=5^20 : (5^15.25)
=5^20 : (5^15.5^2)
=5^20:5^17
=5^3
=125
\(5^{20}:\left(5^{15}.6+5^{15}.19\right)\)
\(=5^{20}:\left[5^{15}.\left(6+19\right)\right]\)
\(=5^{20}:\left(5^{15}.25\right)\)
\(=5^{20}:\left(5^{15}.5^2\right)\)
\(=5^{20}:5^{15+2}\)
\(=5^{20}:5^{17}\)
\(=5^{20-17}\)
\(=5^3\)
\(=125\)
\(5^{20}:\left(5^{15}\cdot6+5^{15}\cdot19\right)\)
= \(5^{20}:5^{15}\cdot6+5^{20}:5^{15}\cdot19\)
= \(5^5\cdot6+5^5\cdot19\)
= \(3125\cdot6+3125\cdot19\)
= \(18750+59375\)
= \(78125\)
