What is the percentage of salt in the solution if 400 g of the solution contains 36 g of salt?

1) Let us take the mass of the entire solution as 100%, and the mass of the salt in this solution as x%.

2) Let’s write briefly:

400 grams of solution – 100%;

36 grams of salt – x%.

3) Based on this, we will compose the proportion:

400: 36 = 100: x.

4) Let’s solve the proportion.

According to its main property, the product of extreme terms is equal to the product of averages, so we write:

400 * x = 36 * 100;

400x = 3600;

x = 3600: 400;

x = 9.

5) We find that 9% of the salt is contained in this solution.

Answer: 9%.