Q25 of 49 Page 1

From a solid cylinder of height 20 cm and diameter 12 cm, a conical cavity of height 8 cm and radius 6 cm is hollowed out. Find the total surface area of the remaining solid.


Radius= Diameter/2 =12/2
Radius=6cm


Height of cylinder=20cm


Height of cone=8cm


Slant height of cone,l=√ h2 + r2


l=√ (8)2 + (6)2


l=√ 64 + 36=√ 100


l=10cm


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


Total surface area=πrl + 2πrhcyl + πr2


=


=cm2


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