The formula for mass, which is mass = density x volume, can be rewritten as volume = mass/density. We can deduce the volume of the cube as the mass and density are given: 17.2g/2.7g/ml = 6.37ml. Now that the volume of the cube is known, we can deduce the edge length. Volume = length x width x height, so 6.37 = X^3. We then take the cube root of 6.37 to discover the value of x, which will be the edge length of the cube. The edge length of the cube is 1.85 cm.