Q28 of 39 Page 1

A bucket open at the top is in the form of a frustum of a cone with a capacity of 12308.8 cm3. The radii of the top and bottom of circular ends of the bucket are 20 cm and 12 cm respectively. Find the height of the bucket and also the area of the metal sheet used in making it.(Use π = 3.14)

Volume of the bucket = 12308.8 cm3

Radius of top r1 = 20 cm


Radius of bottom r2 = 12 cm


Volume of Bucket






h = 5 × 3

h = 15 cm

Surface area of the metal sheet used = πr22 + π(r1+r2)l

  
 

 = √289

 =17 cm

Surface area of the metal sheet = π(12)2 + π(20+12)17

= 3.14×144 + 3.14×32×17
= 3.14(144 + 32×17)
= 3.14 (144 + 544)
= 3.14 (688)

= 2160.32 cm2

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