Question 29301
If 40mL of the solution is 50% acid, that means that the solution is made of 20mL pure acid. 10% of what number is 20? Write 0.1x=20 Divide both sides by 0.1 to get x=200  So you need a total of 200mL of liquid, since you've already got 40mL, 200-40=160 mL of water you still need.