Answer:
we will mix 55 liters of 20% solution and 20 Liters of 50% solutions.
Step-by-step explanation:
let the 20% solution = x liters
let the 50% solution = y liters
total solution of the mixture of the two solutions in % = 28%
total solution of the mixture of the two solutions in liters = 75 liters
considering the total solutions given, we will have the following equations if we mix the solutions in equal proportion;
20x + 50y = 28 (75)
0.2x + 0.5y = 0.28(75)
0.2x + 0.5y = 21 -------equation 1
Also,
x + y = 75 ------equation 2
y = 75 - x
(substitute this into equation 1)
0.2x + 0.5(75 - x) = 21
0.2x + 37.5 - 0.5x = 21
0.2x - 0.5x = 21 - 37.5
-0.3x = -16.5
x = -16.5 / -0.3
x = 55 liters
Recall, y = 75 - x
y = 75 -55
y = 20 Liters
Thus, we will mix 55 liters of 20% solution and 20 Liters of 50% solutions.