`{81^{4} . 15^{3} . 5^{2}}/{27^{3} . 5^{9}}`
`= {(3^{4})^{4} . (3.5)^{3} . 5^{2}}/{(3^{3})^{3} . 5^{9}}`
`= {3^{16} . 3^{3} . 5^{3} . 5^{2}}/{3^{9} . 5^{9}}`
`= {3^{19} . 5^{5}}/{3^{9} . 5^{9}}`
`= {3^{10} . 1}/{1 . 5^{4}}`
`= {3^{10}}/{5^{4}}`
`= 59049/625`