Q29 of 30 Page 1

The radii of circular ends of a bucket of height 24 cm are 15 cm and 5 cm. Find the area of its curved surface.

First, we will draw the bucket as per the given data,



Given the height of the bucket, h = 24cm


Radius of the upper end, r1 = 15cm


Radius of the lower end, r2 = 5cm


So, the slant height, l of the bucket can be calculated using the below formula



Now substituting the corresponding values, we get






l = 26cm


Now we know the curved surface area of a frustum is


= π(r1 + r2)l


Substituting the corresponding values, we get


= π (15 + 5) (26)


= π (20) (26)


= π (520)


= 3.14 × 520


= 1632.8≈ 1633cm2


Hence the curved surface area of the bucket is 1633cm2.


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