16 glass spheres each of radius 2 cm are packed in a cuboidal box of internal dimensions 16 cm × 8 cm × 8 cm and then the box is filled with water. Find the volume of the water filled in the box.

Volume of the box = 16 cm × 8 cm × 8 cm = 1024 cm³.

Radius of the glass sphere, r = 2 cm.

Volume of the sphere = $\dfrac{4}{3}πr^3$

Volume of sphere = $\dfrac{4}{3} \times \dfrac{22}{7} \times 2^3$

$= \dfrac{4 \times 22 \times 8}{3 \times 7} \\[1em] = \dfrac{704}{21} \text{cm}^3.$

Volume of 16 spheres = 16 $\times \dfrac{704}{21} = \dfrac{11264}{21} = 536.38\text{ cm}^3$.

Volume of water filled in box = Volume of the box - Volume of 16 spheres = 1024 - 536.38 = 487.62 cm³.

Hence, the volume of the water filled in the box is approximately 487.6 cm³.