You need a 40% alcohol solution. On hand, you have a 600 mL of a 85% alcohol mixture. How much pure water will you need to add to obtain the desired solution?

Write an equation using the information as it is given above that can be used to solve this problem. Use x as your variable to represent the amount of pure water you need to use.

Solution:

x pure water will you need to add to obtain the desired solution

So

600*85% = (600+x)*40%

S0

x = 675

So 675 ml pure water will you need to add to obtain the desired solution