Verified answer

(x,y,z) d.p. (2,3,7).

x/2=y/3=z/7=k

a)Aratati ca x=40%(x+y)

x=2k. y=3k z=7k

x+y=2k+3k=5k

5k______100%

2k_______ ?=

2k100/5k=40%

b)Afla x, y, z daca x+2y+7z=104

k(2+6+49)=104

k=104/57

x= 208/57

y=312/57

z= 728/57