Q18 of 49 Page 1

A toy is in the form of a cone mounted on a hemisphere of same radius 7 cm. If the total height of the toy is 31 cm, find its total surface area. [Use π = 22/7]


Given, Height of the toy = 31 cm


Radius = 7 cm


⸫ Height of the cone = 31 – 7 = 24 cm


⸫ Slant height = l =


= 25 cm


⸫ Total surface area of the toy = Surface area of cone + Surface area of hemisphere


= πrl + 2πr2


=


= 550 + 308 = 858 cm2


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