Question

How many liters of a 15% salt solution must be mixed with 5 liters of a 65% salt solution to give a 25% solution?Select one: a. 5 litersb .20 litersC.50 litersd. 13 liters

Answer 1

Let amount of 15% solution be x

Amount of 65% solution is 5L

So after mixing both concentration solutions the net volume will be (5+x).

We could write the following equation:

`\begin{gathered} 15x+65(5)=(5+x)\cdot25 \\ 15x+325=125+25x \\ 200=10x \\ x=20 \end{gathered}`

Therefore, the correct option is B. 20 liters.