Answer:
135 litres
Explanation:
Key concept:
Remember that law,conservation of mass,which says
- Mass before chemical change = mass after chemical change
Let the amount of alcohol to be mixed be x L.
According to the question,
10*x/100 + 90*60/100 = 30 * (90 + x) /100
Solve the particulated equation, and solve for x:
- 10x/100 + 54 = 30(90+x)/100
- (10x +5400)/100 = (2700 + 30x)/100 ( take LCM on LHS)
- 10x + 5400 = 2700 +30x( 100 on the denominator get cancelled which is on both side)
- 20x = 2700 (take 10x to RHS and 2700 to LHS)
- x = 2700/20 = 270/2 = 135 (transpose 20 to RHS)
- x = 135 L
Hence, 135 litres of alcohol solution with 90liters of a 60% solution to get a 30% solution.