The question requires us to calculate the density, in g/mL, of an object, given its mass (10g) and the displacement it caused when put in water (50 mL of water became 56 mL).
The density of an object is defined as its mass divided by its volume:
The mass of the object was provided by the question (10g), and we can calculate the volume of this object from the displacement it caused when put in water: the water level rose 6 mL (56 - 50 = 6 mL) when the object was placed in the water, thus the volume of this object is 6 mL.
Now, we can calculate the density of the object as:
Therefore, the density of the metal object is 1.67 g/mL.