Question

An open metal bucket is in the shape of a frustum of a cone if the diameter

Answer 1

Answer:

Area of metallic sheet used = CSA of Frustum + CSA of Cylinder + CSA of Base

CSA of Frustum -

Diameter of the bigger circular end = 45 cm

Radius = 45/2 = 22.5 cm

Diameter of the smaller circular end = 25 cm

Radius = 25/2 = 12.5 cm

Height of the frustum = Total height of the bucket - Height of the circular base 

⇒ 40 - 6 = 34 cm

Slant Height = l √h² + (r1² - r2²)²

⇒ √34² + (22.5 - 12.5)²

⇒ √1156 + (10)²

⇒ √1156 + 100

⇒ √1256

⇒ Slant Height = 35.44 cm

CSA of Frustum = π(r1 + r2)l

⇒ 22/7*(22.5 + 12.5)*35.44

⇒ 22/7*35*35.44

= 3898.4 cm²

Area of Circular Base -

Base is a circular part with radius 25/2 = 12.5 cm

Area of circular base = πr²

⇒ 22/7*12.5*12.5

491.07 cm²

CSA of Cylinder = 2πrh

⇒ 2*22/7*12.5*6

⇒ 471.428

Area of metallic sheet used = 3898.4 cm² + 491.07 cm² + 471.428

= 4860.898 cm²