.
How many liters of water should be evaporated from 160 liters of a 12% saline solution
so that the solution that remains is a 20% saline solution?
~~~~~~~~~~~~~~~~~~~
I will tell you everything related to this problem,
in order for you do understand the process.
In this problem, concentration is the ratio of the salt mass in kilograms
to the water volume in liters (the salt itself does not add to the volume of the mixture).
So, 160 liters of the 12% saline solution contain 0.12*160 = 19.2 kilograms of salt.
When the water evaporates, the volume of the mixture decreases accordingly,
but the amount of salt in it remains unchangeable.
In order for the 19.2 kg of salt form 20% solution, the volume of the mixture must be
= = 96 liters.
It means that 160-96 = 64 liters of water must evaporate, which gives you the ANSWER.
Solved.
-----------------
It is a standard and typical mixture problem.
For introductory lessons covering various types of mixture word problems see
- Mixture problems
- More Mixture problems
- Solving typical word problems on mixtures for solutions
- Typical word problems on mixtures from the archive
- Special type mixture problems on DILUTION adding water
- Increasing concentration of an acid solution by adding pure acid
- How much water must be evaporated
in this site.
You will find there ALL TYPICAL mixture problems with different methods of solutions,
explained at different levels of detalization, from very detailed to very short.
Read them and become an expert in solution mixture word problems.
Also, you have this free of charge online textbook in ALGEBRA-I in this site
- ALGEBRA-I - YOUR ONLINE TEXTBOOK.
The referred lessons are the part of this textbook in the section "Word problems" under the topic "Mixture problems".
Save the link to this online textbook together with its description
Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson
to your archive and use it when it is needed.