Răspuns :
f+b=120, f= 20/100•b=1/5•b=b/5, inlocuim si obtinem b/5+b=120, amplificam b cu 5 si avem b/5+5b/5=120, 6b/5=120, 6b=120•5, 6b=600, b=100.
[tex]x+y=120[/tex]
[tex]x= \frac{20y}{100} = \frac{y}{5} [/tex]
[tex] \frac{y}{5} +x=120[/tex]
[tex] \frac{(y+5y)}{5} =120[/tex]
[tex] \frac{6b}{5} =120[/tex]
[tex]y=120* \frac{5}{6} [/tex]
[tex]y=100[/tex]
[tex]x= \frac{y}{5} [/tex]
[tex]x= \frac{100}{5} [/tex]
[tex]x=20[/tex]
Raspuns: Numarul barbatilor=100.
[tex]x= \frac{20y}{100} = \frac{y}{5} [/tex]
[tex] \frac{y}{5} +x=120[/tex]
[tex] \frac{(y+5y)}{5} =120[/tex]
[tex] \frac{6b}{5} =120[/tex]
[tex]y=120* \frac{5}{6} [/tex]
[tex]y=100[/tex]
[tex]x= \frac{y}{5} [/tex]
[tex]x= \frac{100}{5} [/tex]
[tex]x=20[/tex]
Raspuns: Numarul barbatilor=100.