Răspuns:
100Kg Au impur.......95kg aur.......5kgAg
2kg..................................x......................y
x=1,9kg Au
y= 0,1kgAg
sau, aplicand formula puritatii
p=m,px100/mi----> mp=95x2/100kg=1,9kg
m,i=m,p + m,impuritati
2= 1,9+m,Ag-----> mAg=0,1kg
Explicație: