SOLUTION: How many quarts of pure alcohol must be added to 10 quarts of a 15% alcohol solution to obtain a mixture which is 25% alcohol? All percentage are by volume. please help me.....

Algebra ->  Coordinate Systems and Linear Equations  -> Linear Equations and Systems Word Problems -> SOLUTION: How many quarts of pure alcohol must be added to 10 quarts of a 15% alcohol solution to obtain a mixture which is 25% alcohol? All percentage are by volume. please help me.....      Log On


   

Question 666677: How many quarts of pure alcohol must be added to 10 quarts of a 15% alcohol solution to obtain a mixture which is 25% alcohol? All percentage are by volume.
please help me.....
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

How many quartshighlight%28x%29 of pure alcohol must be added to 10 quarts of a 15% alcohol solution 

to obtain a mixture which is 25% alcohol? 

Translatethe 'Mixing' into an equation***expressing ALL in terms of alcohol

  x+%2B+.15%2A10qt+=+.25%2810qt+%2B+x%29  || Solve for x

          .75x = .10·10

             x = 1.3 qt