A can contains a mixture of two liquids A and B is the ratio 7 5 When 9 liters of mixture is drawn o...........

Quantitative Aptitude (RBI Grade B) Ratio, Proportion

A can contains a mixture of two liquids A and B is the ratio 7 : 5. When 9 liters of mixture is drawn off and the can is filled with B, the ratio of A and B becomes 7 : 9. How many liters of liquid A was contained by the can initially?