Q9 of 63 Page 20

A heap of wheat is in the form of a cone of diameter 9 m and height 3.5 m. Find its volume. How much canvas cloth is required to just cover the heap? (Use π =3.14)

We have,


r adius = 9/2 = 4.5 m


height = 3.5 m


∴slant height l == = 5.70 m


∴ Volume of the heap =


= ×3.14×(4.5)2×3.5 = 74.1825 m3


Area of canvas required = πrl


= 3.14×4.5×5.7 m2 = 80.54 m2


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