Mixed 22 kg of a 15% acid solution and 18 kg of a 25% solution of the same acid.

Mixed 22 kg of a 15% acid solution and 18 kg of a 25% solution of the same acid. Determine the concentration of the new solution.

1) Find how much pure acid is contained in 22 kg of a 15% acid solution:

22 * 15% = 22 * 0.15 = 3.3 kg.

2) Find how much pure acid is contained in 18 kg of a 25% acid solution:

18 * 25% = 18 * 0.25 = 4.5 kg.

3) Find how many kilograms of pure acid are in the new solution:

3.3 + 4.5 = 7.8 kg.

4) Find the weight of the new solution:

22 + 18 = 40 kg.

5) Determine the concentration of the new solution:

7.8 * 100% / 40 = 19.5%.

Answer: The concentration of acid in the new solution is 19.5%.