Urgentă dau coroana!!!!

Răspuns:
[tex] \frac{x}{2} = \frac{y}{11} = \frac{z}{7} [/tex]
[tex]x + y + z = 80[/tex]
[tex] \frac{x + y + z}{2 + 11 + 7} = \frac{80}{20} = 4[/tex]
x=8. y=44 z=28
2)(x+y+z)/(6+7+8)=20/21
x=40/7
y=20/3
z=160/21