10 liters are drawn from a cask full of wine and is then filled with water. This operation is performed one more time . The ratio of the quantity of wine now left in cask to that of the water is 4:5. How much wine did the cask hold originally?	Select the correct option
A) 10
B) 20
C) 30
D) 45
E) 60
Let the quantity of wine in the cask originally be x liters   quantity of wine left in cask after 2 operations = x(1 - 10/x)^2 liters   x(1 - 10/x)^2 /x = 4/9   (1-10/x)^2 = (2/3)^2   x = 30   Answer is 30
<result>C</result>
10 liters are drawn from a cask full of wine and is then filled with water. This operation is performed one more time . The ratio of the quantity of wine now left in cask to that of the water is 4:5. How much wine did the cask hold originally?