Question

O firma are 120 de angajati.Determinati numarul barbatilor angajati in firma,stiind ca nr femeilor reprezinta 20% din nr barbatilor

Answer 1

$\left \{ {{x+y=120} \atop {y* \frac{20}{100} =x}} \right. <=> \left \{ {{x+y=120} \atop {y* \frac{1}{5} =x}} \right.<=> \left \{ {{x+y=120} \atop {\frac{y}{5} =x}} \right.$ <=>
$<=> \left \{ {{x+y=120} \atop {y=5x}} \right.<=> \left \{ {{x+5x=120} \atop {y=5x}} \right.$<=>
$<=> \left \{ {{6x=120} \atop {y=5x}} \right.<=> \left \{ {{x=20} \atop {y=5*20}} \right.<=> \left \{ {{x=20} \atop {y=100}} \right.$