Question 748971
.30X+.15(20-X)=.195*20
.30X+3-.15X=3.9
.15X=3.9-3
.15X=.9
X=.9/.15
X=6 LITERS OF 30% MIX IS USED.
PROOF:
.30*6+.15(20-6)=.15*20
1.8+.15*14=3.9
1.8+2.1=3.9
3.9=3.9