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Question
The radii of the circular ends of a solid frustum of a cone are 33 cm and 27 cm and its slant height is 10 cm. Find its total surface area.
Solution
The slant height of the frustum of a cone is l=10cm. The radii of the upper and lower circles of the bucket are r1 =33cm and r2 =27cm respectively.
The total surface area of the frustum of the cone is
`S_1 = pi (r_1 + r_2) xx l + pir_1^2 + pir_1^2`
` = pi xx (33 + 27) xx 10 + pi xx 33^2 + pi xx 27^2`
` = 600pi + 1089pi + 729pi`
` = 7599.42 cm^2`
Hence total surface area is `= 7599.42 cm^2`
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