1.  A vessel is filled with liquid, 3 parts of which are water and 5 parts syrup. How much of the mixture must be drawn off and replaced with water so that the mixture may be half water and half syrup? 

Answer: Option C Explanation: Suppose the vessel initially contains 8 litres of liquid. Let x litres of this liquid be replaced with water.
5x + 24 = 40  5x 10x = 16
