A sample containing 0.0750 pounds of metal pellets is poured into a graduated cylinder initially containing 22.4 mL of water. The water level rises to 31.3 mL. calculated the density of the metal.

If you want it in pounds/cc it is 0.0750/volume and volume is 31.3-22.4; otherwise convert pounds to grams. There are 453.59 grams in one pound.