primul numar a |----------| 13
al doilea numar b = a*2 + 13 |--------|--------|----------------|
al treilea numar c= b*2+13= 2*(a*2+13)+13= 4*a+26+13=4*a+39
26 13
c |--------|-------|-------|--------|--------------------------|-------|
346-26-13-13 =294
294:7= 42
a=42
b=42*2+13= 84+13=97
c=97*2+13=207
proba : a+b+c= 42+97+207=346