SOLUTION: A biologist has two brine solutions, one containing 3% salt and another containing 12% salt. How many milliliters of each solution should she mix to obtain 1 L of a solution that c

Algebra ->  Customizable Word Problem Solvers  -> Mixtures -> SOLUTION: A biologist has two brine solutions, one containing 3% salt and another containing 12% salt. How many milliliters of each solution should she mix to obtain 1 L of a solution that c      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 517486: A biologist has two brine solutions, one containing 3% salt and another containing 12% salt. How many milliliters of each solution should she mix to obtain 1 L of a solution that contains 8.4% salt?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
A biologist has two brine solutions, one containing 3% salt and another containing 12% salt.
How many milliliters of each solution should she mix to obtain 1 L of a solution that contains 8.4% salt?
:
Let x = amt of 12% brine
the total is required to be 1 liter, therefore
(1-x) = amt of 3%
:
.12x + .03(1-x) = .084(1)
.12x + .03 - .03x = .084
.12x - .03x = .084 - .03
.09x = .054
x = .054/.09
x = .6 liters of 12%
then
1-.6 = .4 liters of 3%