A fez, the cap used by the Turks, is shaped like the frustum of a cone (see Fig. 13.24). If its radius on the open side is 10 cm, radius at the upper base is 4 cm and its slant height is 15 cm, find the area of material used for making it
Given:
Radius (r2) at upper circular end = 4 cm
Radius (r1) at lower circular end = 10 cm
Slant height (l) of frustum = 15 cm
Area of material used for making the fez = CSA of frustum + Area of upper circular end
= π (r1 + r2) l + πr22
= π (10 + 4) * 15 + π (4)2
= π (14) * 15 + 16π
= 210π + 16π
= 
= 710 
cm2
Hence, the area of material used= 710 
cm2
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