# The diameter of a roller is 84 cm and its length is 120 cm . I t takes 500 complete revolution to move once over to level a playground . find the area of then playground in m square .

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by unknown808

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by unknown808

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height = 120 cm = 1.2 m

So, CSA = 2πrh = 2* π * 0.42 * 1.2 = 31.680 m²

This is the area of taking one revolutio

Now, the area of taking 500 revolution = area of ground

so, area of ground = 31.68 * 500 = 5184 m²

= 2*22/7*42*120

=2*22*6*120

=12*22*120

=31680 cm^2

area of playground

= 500* 31680 = 1584000 cm^2