Question 215279
.08x+.20*40=.12(40+x)
.08x+8=4.8-.12x
.08x-.12x=4.8-8
-.04x=-3.2
x=-3.2/.04
x=80 ml of 8% salt is used.
Proof:
.08*80+.20*40=.12(40+80)
6.4+8=.12*120
14.4=14.4