Răspuns:
se aplica relatia
c=mdx100/ms, unde ms= md+m,apa
md=400g
ms= 400g+1200g=1600g
c= 400x100/1600=25%
presupunem ca plecam de la md=400g zahar
ms= mdx100/c=400x100/40g= 1000g
m,apa= ms-md= 1000g-400g=600g -< aceasta este masa de apa necesara
Explicație:
