A pot contains 6 L of brine at a concentration of 110 g/L. How much of the water should be boiled off to increase the concentration to 200 g/L?

The correct answer to the question is 2.7 Liters of water, that is;

to increase the concentration to 200 g/L,  2.7 L of water should be boiled off

Explanation:

To solve this we list out the known variables

We note the concentration of brine = 110 g/L

That is each liter of brine contains 110 g of solute

To increase the concentration to 200 g/L we have

6 liters of brine containing 6 L × 110 g/L = x L of 200 g or solute salt

to have 200 g

660 = 200 × x or x liters = 660/20 = 3.3 L

However to arrive at the concentration, then 6 L - 3.3 L must be boiled off thus 2.7 L must be boiled off to increase the concentration to 200 g/L.