Professor Beaker has a 50-milliliter solution containing 60% acid. How many milliliters of pure water should he add to this solution to produce a solution containing 40% acid?

Answer 1

see related questions below.

Answer 2

I've tried looking at similar problems but I'm still confused.

Answer 3

the amount of acid in the parts must add up to the amount in the final mix. If x ml of water (0% acid) are added, then you need

.60*50 + 0x = .40(50+x)

Now just solve for x. This assume you know what "%" means ...