# How much of each type should a farmer mix to obtain 100 liters of fertilizer in a 12% solution if he has fertilizer in 5% and 15% solutions?

##### 1 Answer

What we can do here is to apply **material balance**. What comes in must come out.

**X** and **Y** represents the volume of each fertilizer that the farmers need to mix in order to form **12% of 100 liters of solution**.

Observe the arrows pointing to the **VESSEL** and the arrows pointing away from the **VESSEL.**

**Arrows pointing to the vessel means it goes in.
Arrows pointing away from the vessel means it goes out.**

**OVERALL MATERIAL BALANCE**

What goes in = What comes out

**Fertilizer Balance**

Simplifying

from

**Substitute Y in the fertilizer balance**

divide both sides by -0.1

**liters of 5% fertilizer**

I hope this helped you.