A cane contains a mixture of two liquids A and B in the ratio 7 : 5. When 9 litres of mixture are drawn off and the cane is filled with B, the ratio of A and B becomes 7 : 9. How many litres of liquid A was contained by the cane initially?
Suppose the cane initially contains 7x and 5x litres of mixtures A and B respectively.
Quantity of A in mixture left
=
Quantity of B in mixture left
=
⇒ 252 x – 189 = 140 x + 147
⇒ 112 x = 336
⇒ x = 3.
So, the cane contained 21 litres of A.