Question 166784: How much water should be added to 30 gallon of a solution that is 70% antifreeze to bring the antifreeze percentage down to 60%. Found 2 solutions by stanbon, josmiceli:Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
How much water should be added to 30 gallon of a solution that is 70% antifreeze to bring the antifreeze percentage down to 60%.
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antifreeze + antifreeze = antifreeze
0.70*30 + 0*x = 0.60(30+x)
Multiply thru by 100 to get:
70*30 + 0 = 60(30+x)
2100 = 1800 + 60x
60x = 300
x = 5 gallons (amount of pure water hat should be added to the mixture )
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Cheers,
Stan
You can put this solution on YOUR website! In words:
(gallons of antifreeze in final solution)/(gallons of solution) = % antifreeze
Let = the gallons of water to be added
The gallons of final solution will be
Initially there is 70% antifreeze gallons
5 gallons of water must be added to get a 60% solution
check:
OK
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