Question

How many kilograms of 30% salt solution by mass and 40% salt solution by mass

should be mixed to form 200 kg of 37% salt solution by mass?

Answer 1

60 kilograms of the 30% solution

140 kilograms of the 40% solution

Explanation:

Let x = the no. of kilos containing 30% salt (solution 1)

and 200 - x = the no. of kilos containging 40% salt solution 2)

.30x = amount of salt in solution 1

.40(200 - x) = amount of salt in solution 2

.37(200) = amount of salt in the final mixture

salt in solution 1 + salt in solution 2 = salt in final mix.

.30x + .40(200 - x) = .37(200)

Let's multiply thru the equation by 100 to remove the decimal fractions

30x + 40(200 - x) = 37(200)

30x + 8000 - 40x = 7400

-10x = -600

x = 60 kilograms of the 30% solution

200 - 60 = 140 kilograms of the 40% solution