# The radius and height of a cone are in the ratio 4 : 3. The volume of the cone is 539/2 cm3 . Find its curved surface area.

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by palashk

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by palashk

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height = 3x

volume = 539/2 cm³

but volume of cone = 1/3 pi r² h

539/2 = 1/3. 22/7.16x² . 3x

539/2.3.7/22 = 48x³

∴x³=7.7.7/4.4.4

x = 7/4

∴surface area of cone =pi r l

but l=√h²+r²

√9x²+16x²

√25x²

5x

5.7/4

35/4

surface area = 22/7. 7/4 . 35/4

=385/8 units²