NECO 2022 · Paper 1 · Q48

A plastic spherical ball of radius 6 cm was melted and reshaped into a cube. Find the length of the cube, correct to the nearest centimetre.

Worked solution (try it first)

The volume of the ball is $\frac{4}{3} \times \frac{22}{7} \times 6^3 \approx 905.1\text{ cm}^3$ .
The cube has the same volume, so its edge is $\sqrt[3]{905.1} \approx 9.67$ cm.
To the nearest centimetre that is 10 cm, option D.