What length of tarpaulin 3 m wide will be required to make conical tent of height 8 m and base radius 6 m? Assume that the extra length of material that will be required for stitching margins and wastage in cutting is approximately 20 cm (Use π = 3.14)

The diagram is given as:



Height (h) = 8m


Radius (r) = 6m


Now, we know that, 


According to Pythagoras theorem, l2 = r2 + h2


⇒ l2 = 62 + 82


⇒ l2 = (62 + 82)


⇒ l2 = 36 + 64


⇒ l2 = 100


⇒ l = √100 = 10 m


CSA of conical tent = πrl


= π × 6m × 10 m


= 22/7 × 6m × 10 m


= 188.57 m2


≈ 186 m2


Now, Let the length of tarpaulin sheet required be "x" m


 


As 20 cm will be wasted, therefore, the effective length will be = (x − 20 cm) =  (x − 0.2 m)


Breadth of tarpaulin = 3 m


 


Area of sheet = CSA of tent


⇒ [(x − 0.2 m) × 3] m = 188.4 m2


⇒ x − 0.2 m = 62.8 m


⇒x = 63 m


 


Therefore, the length of the required tarpaulin sheet will be 63 m


 

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