va rog am test dau ce vreti

5.md=40g soda
mapa = 260g
ms = md + mapa
ms = 40g + 260g
ms =300g solutie
c = md/ ms x100
c = 40 /300 x100
c= 13,33%
6.c/100=md/ms => md=c*ms/100=5*300/100=15 g substanta dizolvata in solutie