This question was asked in 2012 cbse board exam. Question from RS Aggarwal book chapter volume and surface area of solid, page number 829, exercise 17D, problem number 35

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# A toy is in the form of a cone of radius 3.5 cm mounted on a hemisphere of same radius. The total height of the toy is 15.5 cm. Find the total surface area of the toy.

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ht of toy=15.5 cm (given)

ht of hemisphere=3.5 cm

ht of cone=15.5-3.5

=12cm

slant ht. of cone=under root h^2+r^2

=under root (12^2+3.5^2)

=under root 144+12.25

=under root 156.25

= 12.5 cm

CSA oc hemisphere=2×22/7×(3.5)^2

=77 cm^2

CSA of cone=22/7×3.5×12.5

=137.5 cm^2

TSA of toy=CSA of hemisphere+CSA of cone

=77+137.5

=214.5cm^2