SOLUTION: the cooling system in ann's car contains 19 liters of 30% antifreeze. how much coolant must be drained out and replaced with 80% antifreeze so that the system will contain 50% anti
Algebra ->
Customizable Word Problem Solvers
-> Mixtures
-> SOLUTION: the cooling system in ann's car contains 19 liters of 30% antifreeze. how much coolant must be drained out and replaced with 80% antifreeze so that the system will contain 50% anti
Log On
Question 445611: the cooling system in ann's car contains 19 liters of 30% antifreeze. how much coolant must be drained out and replaced with 80% antifreeze so that the system will contain 50% antifreeze. how much of the original coolant will be left in the car? Found 2 solutions by ankor@dixie-net.com, jorel1380:Answer by ankor@dixie-net.com(22740) (Show Source):
You can put this solution on YOUR website! the cooling system in ann's car contains 19 liters of 30% antifreeze.
how much coolant must be drained out and replaced with 80% antifreeze so that
the system will contain 50% antifreeze?
:
Let x = amt of 80% antifreeze added, this is also the amt of 30% antifreeze removed
:
.30(19-x) + .80x = .50(19)
:
5.7 - .3x + .8x = 9.5
:
-.3x + .8x = 9.5 - 5.7
:
.5x = 3.8
x =
x = 7.6 liters of 80% antifreeze added, the same amt of 30% removed
:
how much of the original coolant will be left in the car?
19 - 7.6 = 11.4 liters of 30% antifreeze remain
:
:
Check solution
.3(11.4) + .8(7.6) = 9.5
You can put this solution on YOUR website! x+y=19
.30x+.80y=.5(x+y)
.30x+.80y=.5x+.5y
.3y=.2x
3y=2x
2x+2y=38
3y+2y=38
5y=38
y=38/5
x=57/5
38/5 liters of coolant must be drained and replaced with 80% antifreeze to get the desired mix. 57/5 liters of 30% coolant can be left in the radiator..
