Question

How many liters each of a 15% acid solution and a 60% acid solution must be used to produce 60 Liters of a 30% acid solution?

Answer 1

From the question;

Liters of 15% acid solution + Liters of 60% acid solution = 60 liters of 30% acid solution

Let

Liters of 15% acid solution = x

Then

Liters of 60% acid solution = 60 - x

Therefore we have

`\begin{gathered} (15)/(100)(x)+(60)/(100)(60-x)=(30)/(100)(60) \\ 0.15x+0.6(60-x)=0.3(60) \end{gathered}`

This further gives

`\begin{gathered} 0.15x+3.6-0.6x=1.8 \\ 0.15x-0.6x=1.8-3.6 \\ -0.45x=-1.8 \\ x=(-1.8)/(-0.45) \\ x=4 \end{gathered}`