Use the D = M/V equation, in which Density can be found by dividing Mass/Volume.
To solve, first find a rectangular prism tub that is filled to a certain level. Next, place the rock inside to find the amount of displacement (or how high the water level goes up.) In this way, you can find the volume of the rock.
Next, solve for the Mass. This can be found by dividing the total weight from the gravitational pull. This would give you the mass.
Finally, to find Density, divide the Mass found with the Volume. This would give you your final answer
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