Question

How many milliliters of a 38% salt solution do we need to mix with 5 milliliters of a 30% salt solution sothat the resulting mixture is a 33% salt solution

Answer 1

First, let us frame the equation as follows,

(x ml) of (38% solution ) + (5 ml) of (30% solution ) = (x+5 ml) of (33% solution )

To find the value of x:

On solving we get,

`\begin{gathered} \mleft(x\mright)((38)/(100))+5((30)/(100))=(x+5)((33)/(100)) \\ 38x+150=(x+5)33 \\ 38x+150=33x+165 \\ 38x-33x=165-150 \\ 5x=15 \\ x=3 \end{gathered}`

Therefore, the answer is 3 ml.

That is, 3 milliliters of a 38% salt solution do we need to mix with 5 milliliters of a 30% salt solution so that the resulting mixture is a 33% salt solution.