Question

A chemist have one solution contaning 50% acid & second one contain 25% acid. How much of each should be used to make 10 liter of 40%acid solution?

Answer 1

25 % of the fist one and then 12.5%of the second one.

Answer 2

take 6 litres of the 50% solution and 4 litres of the 25% solution, You will get 10 litres of 40% solution.