SOLUTION: A car radiator has a capacity of 16qts and is filled w/a 25% antifreeze solution. How much must be drained off and replaced w/pure antifreeze to obtain a 40% antifreeze solution?

Question 101977: A car radiator has a capacity of 16qts and is filled w/a 25% antifreeze solution. How much must be drained off and replaced w/pure antifreeze to obtain a 40% antifreeze solution?
Answer by ankor@dixie-net.com(22740) (Show Source): You can put this solution on YOUR website!
A car radiator has a capacity of 16 qts and is filled w/a 25% anti-freeze solution. How much must be drained off and replaced w/pure antifreeze to obtain a 40% anti-freeze solution?
:
Let x = the amt drained and the amt added
:
Drained + Added = required mixture
.25(16-x) + 1.0x = .40(16)
:
4 - .25x + 1x = .40(16)
:
4 + .75x = 6.4
:
.75x = 6.4 - 4
:
.75x = 2.4
:
x = 2.4/.75
:
x = 3.2 gal of pure antifreeze
:
:
Check solution using x = 3.2:
.25(16-3.2) + 3.2 = .40(16)
.25(12.8) + 3.2 = 6.4
3.2 + 3.2 = 6.4
RELATED QUESTIONS
a car radiator has a capacity of 16 quarts and is filled with a 25% antifreeze solution.... (answered by stanbon)

A car radiator has a capacity of 16 quarts and is filled with a 25% antifreeze solution. (answered by nerdybill)

a car radiator has a capacity of 16 quartz and is filled with a 25% antifreeze solution.... (answered by mananth,josgarithmetic,greenestamps)

a car radiator has a capacity of 16 quarts and is filled with a 25% anifreeze solution,... (answered by stanbon)

Weighted Averages. A car radiator has a capacity of 14 quarts and is filled with a... (answered by nerdybill,ptaylor)

A car radiator has a 16 quart capacity and is currently filled with a 40% antifreeze... (answered by nerdybill,josmiceli)

Please help me set up this mixture equation: A car radiator has a capacity of 16 quarts... (answered by scott8148)

the radiator of an car has a capacity of 16 quarts. it is presently filled with a 20%... (answered by josgarithmetic)

A car radiator has a capacity of 16 quarts and is filled with a 25% Anti-freeze solution. (answered by ankor@dixie-net.com)