Jackie has two solutions that are 2 percent sulfuric acid and 12 percent sulfuric acid by volume, respectively. If these solutions are mixed in appropriate quantities to produce 60 liters of a solution that is 5 percent sulfuric acid, approximately how many liters of the 2 percent solution will be required?	Select:
A) 18
B) 20
C) 24
D) 36
E) 42
Use weighted average:   2% and 12% solutions mix to give 5% solution.   w1/w2 = (A2 - Avg)/(Avg - A1) = (12 - 5)/(5 - 2) = 7/3   You need 7 parts of 2% solution and 3 parts of 12% solution to get 10 parts of 5% solution.   If total 5% solution is actually 60 litres, you need  7*6= 
<gadget id="calculator"> 7*6</gadget>
<output>42</output>
42 litres of 2% solution and 3*6= 
<gadget id="calculator">3*6</gadget>
<output>18</output>
18 litres of 12% solution.   Answer (42)
<result>E</result>
Jackie has two solutions that are 2 percent sulfuric acid and 12 percent sulfuric acid by volume, respectively. If these solutions are mixed in appropriate quantities to produce 60 liters of a solution that is 5 percent sulfuric acid, approximately how many liters of the 2 percent solution will be required?