Răspuns:
Explicație pas cu pas:
not, cu x -nr ovinelor
oi: 3/7*x
miei: 4/6*(x-3/7x)=2/3(7/7x-3/7x)=2/3*4/7x=8/21x
berbeci:16
x=oi+miei+berbeci
x=3/7x+8/21x+16
x-3/7x-8/21x=16
21/21x-9/21x-8/21x=336/21
21x-9x-8x=336
4x=336
x=336:4
x=84 (ovine)
