Question

Doua numere proportionale cu 5 si 7 au suma egala cu 156. Atunci numerele sunt:...

Answer 1

$\frac{5}{x}$=$\frac{7}{y}$=k
x=5k
y=7k
5k+7k=156
12k=156
k=156:12
k=13
x=5*13=65
y=7*13=91