A hemispherical bowl is made of brass, 0.25 cm thickness. The inner ra

1.	A hemispherical bowl is made of brass, 0.25 cm thickness. The inner radius of the bowl is 5 cm. Find the ratio of outer surface area to inner surface area.
Answer» Inner radius of the hemisphere ‘r’ = 5 cm Outer radius of the hemisphere ‘R’ = inner radius + thickness = (5 + 0.25) cm = 5.25 cm Ratio of areas = 3πR² : 3πr² = R² : r² = (5.25)² : 5² = 27.5625 : 25 = 1.1025:1 = 11025 : 10000 = 441 : 400

A hemispherical bowl is made of brass, 0.25 cm thickness. The inner radius of the bowl is 5 cm. Find the ratio of outer surface area to inner surface area.

Answer»

Inner radius of the hemisphere ‘r’ = 5 cm

Outer radius of the hemisphere ‘R’

= inner radius + thickness

= (5 + 0.25) cm = 5.25 cm

Ratio of areas = 3πR² : 3πr²

= R² : r²

= (5.25)² : 5²

= 27.5625 : 25

= 1.1025:1

= 11025 : 10000

= 441 : 400