\(\eqalign{
& 3{x^2}y.2{y^2} = \left( {3.2} \right).{x^2}.\left( {y.{y^2}} \right) = 6{x^2}{y^3} \cr
& 6x{y^3}.x = 6.\left( {x.x} \right).{y^3} = 6{x^2}{y^3} \cr} \)
\( \Rightarrow 3{x^2}y.2{y^2} = 6x{y^3}.x\)
Vậy \(\dfrac{{3{x^2}y}}{{6x{y^3}}} = \dfrac{x}{{2{y^2}}}\)