A can contains a mixture of liquids A and B is the ratio 7:5. When 6 litres of mixture are drawn off and the can is filled with B, the ratio of A and B becomes 7:9. How many liter of liquid A was contained by the can initially?
Select
A) 12  B) 18  C) 14  D) 20  E) 22
Ci*Vi = Cf*Vf   (7/12)*(V1 - 6) = (7/16)*V1   (V1 - 6)/V1 = 3/4   6 accounts for the difference of 1 on ratio scale so Initial volume = V1 = 4*6= 
<gadget id="calculator">4*6</gadget>
<output>24</output>
24 litres.   7/12 of the initial mixture was liquid A so liquid A was   (7/12)*24= 
<gadget id="calculator">  (7/12)*24</gadget>
<output>14</output>
14 litres.   Answer : 14
<result>C</result>
A can contains a mixture of liquids A and B is the ratio 7:5. When 6 litres of mixture are drawn off and the can is filled with B, the ratio of A and B becomes 7:9. How many liter of liquid A was contained by the can initially?