Question

chemist has three different acid solutions. The first acid solution contains 15 % acid, the second contains 25 % and the third contains 70 % . They want to use all three solutions to obtain a mixture of 80 liters containing 30 % acid, using 2 times as much of the 70 % solution as the 25 % solution. How many liters of each solution should be used

Answer 1

Answer:

16L of 70% solution

32L of 25% solution

32L of 15% solution

Explanation:

x = volume of 70% acid solution

y = volume of 15% acid solution

2x = volume of 25% acid solution

2x + x + y = 80

3x + y = 80 (×8)

24x + 8y = 640 → 24x = 640 - 8y

0.7x + 0.25(2x) + 0.15y = 0.3(80)

⁷/₁₀.x + ¹/₂.x + ³/₂₀.y = 24

¹²/₁₀.x + ³/₂₀.y = 24 (×20)

24x + 3y = 480

(640 - 8y) + 3y = 480

640 - 5y = 480

5y = 160

y = 32

3x + 32 = 80

3x = 48

x = 16