The formula for the volume of a sphere, V, in terms of its radius, r, is:

V = 4/3πr^{3}

**Example**

Calculate the volume of the sphere shown below in cm^{3} to 3 sig. figs.

**Answer**

Diameter d = 8 cm

Radius r = 8 ÷ 2 = 4 cm

**Volume **= 4/3πr^{3} = 4 ÷ 3 x π x 4^{3} = 268.08.... ≈ **268 cm ^{3} **(3 s.f.)

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