Q29 of 49 Page 1

From a solid cylinder whose height is 15 cm and diameter 16 cm, a conical cavity of the same height and same diameter is hollowed out. Find the total surface area of the remaining slid.


Radius= Diameter/2 =16/2
Radius=8cm


Height=15cm


Slant height of cone,l=√ h2 + r2


l=√ (15)2 + (8)2


l=√ 225 + 64=√ 289


l=17cm


Total surface area of remaining solid= Curved surface area of cone
+ Curved Surface area of cylinder
+ Area of bottom part


Total surface area=πrl + 2πrh + πr2


=3.14 [8 × 17 + 2 × 8 × 15 + 8 × 8]
=3.14 [440] =1381.6cm2


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