Răspuns :
Salut!
a/2=b/5=c/6=k
a=2k
b=5k
c=6k
2a+3b+c=500
2x2k+3x5k+6k=500
4k+15k+6k=500
25k=500
k=20
a=40
b=100
c=120
Succes!
{a, b, c} d. p. {2,5,6} -> a/2=b/5=c/6=k
a/2=k - > a=2k
b/5=k - > b=5k
c/6=k - > c=6k
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2a+3b+c=500
2*2k+3*5k+6k=500
4k+15k+6k=500
25k=500
k=20
a=2k
a=20
b=5k
b=100
c=6k
c=120