SOLUTION: My car's radiator is full of an antifreeze-water mixture that is 75% water and 25% antifreeze. I left the cap off while driving and a lot of the mixture leaked out. I filled up the

Algebra ->  Customizable Word Problem Solvers  -> Mixtures -> SOLUTION: My car's radiator is full of an antifreeze-water mixture that is 75% water and 25% antifreeze. I left the cap off while driving and a lot of the mixture leaked out. I filled up the      Log On

Ad: Over 600 Algebra Word Problems at edhelper.com


   



Question 733592: My car's radiator is full of an antifreeze-water mixture that is 75% water and 25% antifreeze. I left the cap off while driving and a lot of the mixture leaked out. I filled up the radiator with 9 quarts of water as I was out of antifreeze and then foud the mixture was only 12% antifreeze. What is the capacity of the radiator.
I tried setting my problem up as .75(.25)=18.75 and .12(.88)=10.56 This answer got me nowhere and now I am stuck. Please help!

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +x+ = the radiator's capacity in quarts
After losing mixture, +9+ quarts of water filled the radiator,
so +9+ quarts of mixture was lost
-------------
You started with +.25x+ quarts of antifreeze and lost
+.25%2A9+=+2.25+ quarts, so there is +.25x+-+2.25+ quarts
of antifreeze in the radiator before the water is added
-------------
+%28+.25x+-+2.25+%29+%2F+x+=+.12+
+.25x+-+2.25+=+.12x+
+.13x+=+2.25+
+x+=+17.3077+
The capacity of the radiator is 17.3077 quarts
check answer:
There is +.25%2A17.3077+=+4.327+ quarts of antifreeze to start
+.25%2A9+=+2.25+ quarts of antifreeze were lost
+4.327+-+2.25+=+2.077+ quarts of antifreeze left
After water is added,
+2.077+%2F+17.3077+=+.120004+
close enough
Hope I got it