A metal block having an internal cavity weight 110 g in air and 80 g in water. If the density of metal is 5.5 g/cc, then the volume of cavity is:

Weight of block in air = 110 gWeight of block in water = 80 gLoss of weight in water = 110 - 80 = 30 gThis is equal to weight of water displaced; so volume of water displaced = 30 cc (which is the apparent volume of block)Real volume of the material of block = 1105.5= 20 cc∴ Volume of cavity = 30 cc-20 cc = 10 cc