Case study:
In a school chemistry lab, the lab assistant has two bottles of acid solution on his shelf:
Solution A: 55% acid concentration
Solution B: 80% acid concentration
The science teacher wants a 60% acid solution for tomorrow’s experiment that is to be used by the students.
In what ratio should the 55% solution and the 80% solution be mixed to obtain a 60% acid solution?

Question

Case study:
In a school chemistry lab, the lab assistant has two bottles of acid solution on his shelf:

Solution A: 55% acid concentration

Solution B: 80% acid concentration

The science teacher wants a 60% acid solution for tomorrow’s experiment that is to be used by the students.

In what ratio should the 55% solution and the 80% solution be mixed to obtain a 60% acid solution?

KnowledgeBoat · Accepted Answer

Let x be the quantity of 55% solution and y be the quantity of 80% solution.

Required concentration of solution by mixing two solutions = 60%.

∴ 55x + 80y = 60(x + y)

⇒ 55x + 80y = 60x + 60y

⇒ 55x - 60x + 80y - 60y = 0

⇒ -5x + 20y = 0

⇒ 20y = 5x

⇒ $\dfrac{x}{y} = \dfrac{20}{5}$

⇒ $\dfrac{x}{y} = \dfrac{4}{1}$

⇒ x : y = 4 : 1.

Hence, the ratio of 55% solution to 80% solution is 4 : 1.

Mathematics