a)32x125/100=40--------------a->3
b)(x+1)/6=6/9
9(x+1)=36
9x+9=36
9x=27
x=3----------------------------------b->5
c)p=masa,solutiei,care,se,dizolva/masa,totala=30/150
p=1/5=20%-----------------------c->2
d)Din,prima,si,ultima,fractie=>x=105/7.Din,a,doua,si,ultima=>y=70/5
105/7+70/5=(525+490)/35=1015/35=29--------------------d->4