Answer :
Answer:
The technician need to combine 12-liter of pure acid and 36-liter of 20% acid to make a 48-liter of a 40% acid solution.
Step-by-step explanation:
To find the volume of each batch of acid, we can create a system of equations.
Let:
- [tex]x[/tex] = volume of the pure acid (100%)
- [tex]y[/tex] = volume of the 20% acid
Given:
(a) the solution volume = 48-liter
This means the total volume of the 100% acid and the 20% acid equals to 48-liter:
[tex]x+y=48\ ...\ [1][/tex]
(b) the acid volume = 40% × 48-liter
This means the total acid of the 100% acid and the 20% acid equals to 40% × 48-liter:
[tex]100\%\times x+20\%\times y=40\%\times48[/tex]
[tex]x+0.2y=19.2\ ...\ [2][/tex]
By combining [1] & [2]:
[tex]x+y=48[/tex]
[tex]x+0.2y=19.2[/tex]
---------------------- (-)
[tex]0.8y=28.8[/tex]
[tex]y=36[/tex]
By substituting [tex]y=36[/tex] into [1]:
[tex]x+y=48[/tex]
[tex]x+36=38[/tex]
[tex]x=12[/tex]
Hence, the technician need to combine 12-liter of pure acid and 36-liter of 20% acid.