Answer:
8 Liters of 20% acid and 7 Liters of 50% acid
Step-by-step explanation:
Let we mix "x" liters of 20% acid, and
"y" liters of 50% acid
Total is 15 liters, so we can write:
x + y = 15
or x = 15 - y
Then,
We mix x liters of 20% (20/100=0.2) and y liters of 50% (50/100=0.5) acid solution to make 15 liters of 34% (34/100=0.34) solution, we can write:
0.2x + 0.5y = 0.34(15)
This becomes:
[tex]0.2x + 0.5y = 5.1[/tex]
We replace x with what we got in 1st equation and solve for y:
[tex]0.2x + 0.5y = 5.1\\0.2(15-y) + 0.5y = 5.1\\3-0.2y+0.5y=5.1\\0.3y=5.1-3\\0.3y=2.1\\y=\frac{2.1}{0.3}\\y=7[/tex]
We know x = 15 - y, so
x = 15 - 7
x = 8
So, we use 8 Liters of 20% acid and 7 Liters of 50% acid
