A 2% solution of sulfuric acid was mixed with a 12% solution of sulfuric acid to produce an 8% solution. How do you determine how much 2% solution and how much 12% solution were used to produce 10 gallons of 8% solution?

Question

Hazel Anglin · Accepted Answer

The amount of higher concentration used is #60%#
The amount of lower concentration used is #40%#

There is a trick to this that I discovered when my job was blending of different concentrations.

Let the % amount of higher concentration be #x#

Then by ratio

#(12-2)/100=(8-2)/x#

#=>x/6=100/10#

#=>x=6xx10=60%#
'~~~~~~~~~~~~~~~~~~~~~~~
Check:

#(60/100xx12)+(40/100xx2) =8" "#as required

Savannah Anderson · Answer

undefined Let x be the gallons of the 2% solution and y be the gallons of the 12% solution. The system of equations is:

1. x + y = 10 (total gallons)
2. 0.02x + 0.12y = 0.08(10) (acid content)

Solve the system to find the values of x and y.