Calculate the mass fraction of a substance in a solution when 25 g of salt is dissolved in 65 g of water.

Algorithm for solving the problem:
1) Calculation of the mass of the entire solution. To do this, add the mass of water and the mass of salt.
2) Calculation of the mass fraction of dissolved salt. To do this, divide the mass of salt by the mass of the entire solution and multiply by one hundred percent.
Solution:
1) 25 + 65 = 90g.
2) 25/90 * 100 = 27.8% – the answer.