avem: (4x+1)/3 - (3x-1)/4 = 15 - (25-x) <=>
(aducam la numitor comun ... [3;4;5]=60 si amplificam corezpunzator !)
<=> 20*(4x+1) - 12*(3x-1) = 15*60 - 15*(25-x) <=>
(aici in loc de 15*6 trebuia 15*60 !!!)
<=> 80x+20-36x+12=900-375+15x
80x-36x-15x = 900-375--20-12
29x =493
x = 17