Question

Hanumappa and his wife Gangamma are busy making jaggery
out of sugarcane juice. They have processed the sugarcane
juice to make the molasses, which is poured into moulds in
the shape of a frustum of a cone having the diameters of
its two circular faces as 30 cm and 35 cm and the vertical
height of the mould is 14 cm. If each
cm of molasses has mass about 1.2 g, find the mass of the
molasses that can be poured into each mould. (Take pie = 22/7)​

Answer 1

Answer:

volume of half sphere is 2π/3(R^3-r^3)

Answer 2

Answer:

Height of frustum (h) = 14cm

Diameters of frustum = 30cm and 35cm

Radii of frustum (r and R) = 30/2cm and 35/2cm

volume of frustum  = ⅓ πh(R² + r² + Rr)

→ ⅓ × 22/7 × 14[(35/2)² + (30/2)² + 35/2 × 30/2]

→ ⅓ × 22 × 2[1225/4 + 900/4 + 17.5 × 15]

→ ⅓ × 22 × 2[1225/4 + 900/4 + 17.5 × 15]

→  ⅓ × 22 × 2[1225/4 + 900/4 + 262.5]

→ 44/3[1225 + 900 + 1050/4]

→ 44/3 × 3175/4

→ 11 × 1058.3

→ 11641.3 cm³

Each cm³ of molasses has mass about 1.2 g

→ Mass of 11641.3cm³

→ 11641.3 × 1.2

→ 13969.56 g

→ 13969.56/1000  (1kg = 1000g )

→ 13.9kg = 14kg (approx)