Question 568488: How many liters of pure antifreeze (100% solution) must be added to 30 liters of a 15% antifreeze solution to get a 40% antifreeze solution? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! How many liters of pure antifreeze (100% solution) must be added to 30 liters of a 15% antifreeze solution to get a 40% antifreeze solution?
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alcohol + alcohol = alcohol
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1*x + 0.15*30 = 0.40(x+30)
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Multiply thru by 100 to get:
100x + 15*30 = 40*x + 40*30
60x = 25*30
x = (1/2)25 = 12.5 liters (amt. of pure antifreeze needed)
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cheers,
Stan H.
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