A toy is in the shape of a solid cylinder surmounted by a conical top. If the height and diameter of the cylindrical part are 21 cm and 40 cm respectively, and the height of the cone is 15 cm, then find the total surface area of the toy.
Radius= Diameter/2 =40/2
Radius=20cm
Height of cylinder=21cm
Height of cone=15cm
Slant height of cone,l=√ h2 + r2
l=√ (15)2 + (20)2
l=√ 225 + 400=√ 625
l=25cm
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
=3.14[20 × 25 + 2 × 20 × 21 + 20 × 20]
=3.14[1740]=5463.6cm2
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