Question 511410: How much water should be added to 100 liters of 90% alcohol concentration to dilute it to 75% alcohol concentration? Answer by Maths68(1474) (Show Source):
You can put this solution on YOUR website! Solution A
Amount = x
Concentration =0% =0 (It is pure water so concentration of Acohoal wil be zero)
Solution B
Amount = 100
Concentration =90% = 0.9
Resultant Solution
Amount =100+x
Concentration =75%=0.75
[Amount Solution A * Concentration A] + [Amount Solution B * Concentration of B] = Amount of Resultant * Concentration of resultant
(0)x+(0.9)(100)=(100+x)(0.75)
90=75+0.75x
90-75=0.75x
15=0.75x
15/0.075=x
20=x
Solution A
Amount = x =20 liters
Concentration =0% =0 (It is pure water so concentration of Acohoal wil be zero)
Solution B
Amount = 100
Concentration =90% = 0.9
Resultant Solution
Amount =100+x =100+20=120 liters
Concentration =75%=0.75
Result
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20 liters water should be added to 100 liters of 90% alcohol concentration to dilute it to 75% alcohol concentration.
