Question 159806
.75x+.5(1000-x)=.65*1000
.75x+500-.5x=650
.25x=650-500
.25x=150
x=150/.25
x=600 liters of .75% additive.
1000-600=400 liters of 50% additive.
Proof:
.75*600+.5*400=650
450+200=650
650=650