In some quantity of alcohol, 50% of pure alcohol and 30% of is water. If 20liters of pure alcohol is added, then the strength of alcohol solution becomes 20%. The original quantity was?	Pick:  A) 1.42liters  B) 2.5liters  C) 3liters  D) 5.6liters  E) 7liters
Let the original quantity be x liters   alcohol solution in x liters = 30/100 *x = 3x/10 kg   (3x/10)/(x+20) = 20/100   3x = x/5 + 4   14x = 20   x = 1.42liters   1.42litersnswer is 1.42liters
<result>A</result>
In some quantity of alcohol, 50% of pure alcohol and 30% of is water. If 20liters of pure alcohol is added, then the strength of alcohol solution becomes 20%. The original quantity was?