Mixed 3 liters of a 10% aqueous solution of some substance with 12 liters of a 40% solution of the same substance.

Mixed 3 liters of a 10% aqueous solution of some substance with 12 liters of a 40% solution of the same substance. How many% is the concentration of the solution you received?

Let’s find the amount of some substance in the first solution:

3 * 10/100 = 0.3 liters;

Let’s find the amount of some substance in the second solution:

12 * 40/100 = 4.8 liters;

Let’s find how many liters are in the resulting solution:

3 + 12 = 15 liters;

Let’s calculate how many liters of a certain substance are in the resulting solution:

0.3 + 4.8 = 5.1 liters;

Let’s find the concentration of some substance in the resulting solution:

5.1: 15 = 0.34 or 34%.

Answer: 34%.