Question

A metal cuboid of measures 16 cm × 11 cm × 10 cm was melted to make coins. How many coins were made, if the thickness and diameter of each coin was 2 mm and 2 cm respectively? (π = 3.14)

Answer 1

Given:

Length = 16 cm

Width = 11 cm

Height = 10 cm

Volume of cuboid = 16 × 11 × 10 = 1760 cm³

Coin Dimensions:

Diameter = 2 cm ⟹ Radius = 1 cm

Thickness = 2 mm = 0.2 cm

Volume of one coin (cylinder shape)

Vcoin ​= πr²h

= 3.14 × (1)² × 0.2

= 3.14 × 0.2

= 0.628 cm³

Number of coins = `"Volume of cuboid"/"Volume of one coin"`

Number of coins = `1760/0.628`

= 2802.55

2802 coins can be made.