Q16 of 32 Page 13

A tent is cylindrical in shape with a conical top above it. The radius of the base of the tent is 7m. The height of the cylindrical part is 20 m and the height of the conical part is 4 m. Find the area of canvas cloth needed to construct the tent.

Curved surface area of cylindrical part = 2π rh
                                   = 2 ×× 7 × 20
                                   = 880 m2
For finding the surface area of the curved part of the cone we have to find l, the slant height. 
   l  =  cm = = 8.06 cm 
... surface area of curved part of cone = π r l 
                                                        = × 7 × 8.06 m2
                                                        = 177.32 m2
∴ Total area of canvas needed = (880  + 177.32) m2
                                                = 1057.32m2

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