Answer:
Density, d = 5.37 g/cm³
Step-by-step explanation:
Given that,
Diameter of coin is 19.55 mm
Thickness of the cone is 1.55 mm
Mass of the coin is 2.5 g
We need to find its density. Density is equal to mass upon volume. So,

V is volume, V = A d, d is thickness
Radius = d/2 = (1.955/2) cm=0.9775 cm
Thickness, d = 1.55 mm = 0.155 cm

So, the density of the coin is 5.37 g/cm³.