SOLUTION: how many quarts of pure antifreeze must be added to 2 quarts of a 30% antifreeze solution to obtaine a 60% antifreeze solution

Algebra ->  Customizable Word Problem Solvers  -> Mixtures -> SOLUTION: how many quarts of pure antifreeze must be added to 2 quarts of a 30% antifreeze solution to obtaine a 60% antifreeze solution      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


    

Question 657226: how many quarts of pure antifreeze must be added to 2 quarts of a 30% antifreeze solution to obtaine a 60% antifreeze solution
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +x+ = quarts of pure antifreeze needed
+.3%2A2+=+.6+ quarts of pure antifreeze in 30% solution
--------------
+%28+.6+%2B+x+%29+%2F+%28+2+%2B+x+%29+=+.6+
+.6+%2B+x+=+.6%2A%28+2+%2B+x+%29+
+.6+%2B+x+=+1.2+%2B+.6x+
+x+-+.6x+=+1.2+-+.6+
+.4x+=+.6+
+x+=+3%2F2+
1.5 quarts of pure antifreeze must be added
check:
+%28+.6+%2B+x+%29+%2F+%28+2+%2B+x+%29+=+.6+
+%28+.6+%2B+1.5+%29+%2F+%28+2+%2B+1.5+%29+=+.6+
+2.1+%2F+3.5+=+.6+
+2.1+=+.6+%2A+3.5+
+2.1+=+2.1+
OK