Question 594584: how much pure acid should be mixed with 9 gallons of a 50% acid solution in order to get an 80% acid solution Answer by mananth(16946) (Show Source):
You can put this solution on YOUR website! -------------- percent ---------------- Amount
Acid solution 50 ---------------- 9 gallons
Pure Acid 100 ---------------- x gallons
Total 80 ---------------- 9 + x gallons
50*9+100x=80(9+x)
450+100x=720+80x
100x-80x=-450+720
20x=270
/ 20
x = 13.5 gallons Pure Acid
