SOLUTION: Please help In a chemistry class, 6 liters of a 4% silver iodide solution must be mixed with a 10% solution to get a 6% solution. How many liters of the 10% solution are needed

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: Please help In a chemistry class, 6 liters of a 4% silver iodide solution must be mixed with a 10% solution to get a 6% solution. How many liters of the 10% solution are needed      Log On


   



Question 47444: Please help
In a chemistry class, 6 liters of a 4% silver iodide solution must be mixed with a 10% solution to get a 6%
solution. How many liters of the 10% solution are needed?

Answer by longjonsilver(2297) About Me  (Show Source):
You can put this solution on YOUR website!
Mixture questions are all about BEFORE = AFTER since the "BEFORE's" mix to become the "AFTER", so they have to be "equal".

Right, a definition so we know what x is: Let x be the amount of the 10% solution.
Once mixed, how much will we have? we will have (x+6) litres, surely? :-)

BEFORE:
0.04*6 and 0.10x

AFTER:
0.06*(x+6)

So, 0.04*6 + 0.10x = 0.06*(x+6)
0.24 + 0.10x = 0.06x + 0.36
0.24 + 0.04x = 0.36
0.04x = 0.12
x = 0.12/0.04
x = 3litres

jon