Problem #43 · September 8, 2026

Percentages

A solution containing

8\%

salt has a mass of 300 g. How many grams of water must be evaporated for the salt concentration to reach

12\%

WORKED EXAMPLE

Solution

The mass of salt in the solution is

300 \cdot 0{,}08 = 24

g — the amount of salt remains unchanged during evaporation. For

24

g of salt to make up

12\%

of the new solution, the solution must have a mass of

24 : 0{,}12 = 200

g. Therefore,

300 - 200 = 100

g of water must be evaporated.