Ответ:

  1. \[\frac{6x^2y^2}{18x^3y}=\frac{y}{3x}.\]
  2. \[\frac{30p^5q}{120p^3q^3}=\frac{p^2}{4q^2}.\]
  3. \[\frac{9^{15}}{27^9}=\frac{(3^2)^{15}}{(3^3)^9}=\frac{3^{30}}{3^{27}}=3^3=27.\]

Ответ: \(\frac{y}{3x}\); \(\frac{p^2}{4q^2}\); \(27\).