Question

How many silver coins, 1.75 cm. in diameter and of thickness 2 mm, must be melted to form a cuboid of dimensions 5.5 cm × 10 cm × 3.5 cm ?

Answer 1

Diameter of silver coins is 1.75 cm. 

Thickness = 2 mm. 

Measurement of cuboid: 5.5 × 10 × 3.5 cm. 

∴ Let the required silver coins be ‘n’, 

Volume of ‘n’ coins = Volume of cuboid

∴ n = 400 

∴ 400 silver coins are required.