Consider the given expression,
[tex]\frac{12}{5y^3}\div\frac{18}{y^3}[/tex]
Consider the analogy,
[tex]\frac{a}{b}\div\frac{c}{d}=\frac{a}{b}\times\frac{d}{c}[/tex]
Then the given expression becomes,
[tex]\begin{gathered} =\frac{12}{5y^3}\times\frac{y^3}{18} \\ =\frac{2}{5}\times\frac{1}{3} \\ =\frac{2}{15} \end{gathered}[/tex]
Thus, the simplification of the expression gives 2/15.
