Question 238189
.20x+.10(50-x)=.12*50
.20x+5-.10x=6
.10x=6-5
.10x=1
x=1/.1
x=10 liters of 20% alcohol is used.
50-10=40 liters of 10% alcohol is used.
Proof:
.20*10+.10*40=.12*50
2+4=6
6=6