8 litres are drawn from a cask full of wine and is then filled with water. This operation is performed three more times. The ratio of the quantity of wine now left in cask to that of the water is 16 : 65. How much wine the cask hold originally ?  Pick one:
A) 18 litres	B) 24 litres of wine	C) 32 litres	D) 42 litres	E) None
Solution   Let the quantity of the wine in the cask originally be x litres   then, quantity of wine left in cask after 4 operations   = [x(1- 8/x)4] litres.   Therefore x(1- 8/x)4 / x = 16/81 =› (1- 8/x)4 = (2/3)2   =› (x - 8 / x) = 2/3 =› 3x - 24 = 2x =› x = 24.   Answer 24 litres of wine
<result>B</result>
8 litres are drawn from a cask full of wine and is then filled with water. This operation is performed three more times. The ratio of the quantity of wine now left in cask to that of the water is 16 : 65. How much wine the cask hold originally ?