Explicación paso a paso:
[tex]ro = x \\ mar = y \\ \left \{ \frac{x}{y} = \frac{3}{2} \atop x + y = 80 \right. \\ x = \frac{3y}{2 } \\ \frac{3y}{2} + y = 80 \\ 3y + 2y = 2 \times 80 \\ 5y = 160 \\ y = \frac{160}{5} \\ y = 32 \\ x = \frac{3 \times 32}{2} \\ x = 48[/tex]
