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Probability

Question
CBSEENMA9003439

A cylindrical tent has a conical top with dimension as shown in the figure. Calculate the total cost of the canvas required to make the tent, if the cost of canvas is र 50 per sq. m.

Solution

For cone
Base radius (r) = 8 m
Height (h) = 6m
therefore space space Slant space height space left parenthesis straight l right parenthesis space equals space square root of straight r squared plus straight h squared end root
space space space space space space space space space space space space space space space space space space space space space space space space space equals space square root of left parenthesis 8 right parenthesis squared plus left parenthesis 6 right parenthesis squared end root

= 10 m
∴ Curved surface area = πrl = π(8)(10) = 80π m2


For cylinder
Base radius (R) = 8 m Height (H) = 14 m
∴ Curved surface area = 2πRH = 2 ⋅ π ⋅ 8 ⋅ 14 = 224π m2 Total curved surface area = Curved surface area of the cone + Curved surface area of the cylinder
= 80π + 224π = 304π m2 = 304 x 3.14 m2 = 954.56 m2
∴ Cost of canvas = 954.56 x 50 = र 47728


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