Question 264138
.65x+.40(20-x)=.50*20
.65x+8-.40x=10
.25x=10-8
.25x=2
x=2/.25
x=8 gallons of 65% solution is used.
20-8=12 gallons of 40% solution is used.
Proof:
.65*8+.40*12=.50*20
5.2+4.8=10
10=10