SOLUTION: A car radiator has a capacity of 8 quarts of coolant which is 20% antifreeze. A mechanic needs to drain part of the radiator fluid and replace it with 100% antifreeze to bring the

Question 236325: A car radiator has a capacity of 8 quarts of coolant which is 20% antifreeze. A mechanic needs to drain part of the radiator fluid and replace it with 100% antifreeze to bring the coolant in the system to 60% antifreeze. How much of the original coolant should be drained and replaced by 100% antifreeze to achieve the desired mix?
Answer by nerdybill(7384) (Show Source): You can put this solution on YOUR website!
A car radiator has a capacity of 8 quarts of coolant which is 20% antifreeze. A mechanic needs to drain part of the radiator fluid and replace it with 100% antifreeze to bring the coolant in the system to 60% antifreeze. How much of the original coolant should be drained and replaced by 100% antifreeze to achieve the desired mix?
.
Let x = amount drained and replaced by 100% antifreeze
then
.20(8-x) + x = .60(8)
1.6 - .20x + x = 4.8
1.6 + .80x = 4.8
.80x = 3.2
x = 4 quarts

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

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

A mechanic needs a radiator to have 30% antifreeze solution. The radiator currently is... (answered by josgarithmetic)

A mechanic is working on a car with a 20-qt radiator containing a 60% antifreeze... (answered by checkley71)

A mechanic is working on a car with a 20-qt radiator containing a 60% antifreeze... (answered by josmiceli)

The capacity of a car radiator is 20 quarts. If it�s full of a 55% antifreeze solution,... (answered by josmiceli,Edwin McCravy)

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

The capacity of a car radiator is 18 quarts. If it is full of a 20% antifreeze solution,... (answered by galactus)