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प्रश्न
The hollow sphere, in which the circus motor cyclist performs his stunts, has a diameter of 7 m. Find the area available to the motorcyclist for riding.
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उत्तर
In the given problem, the area available for the motorcyclist for riding will be equal to the surface area of the hollow sphere. So here, we have to find the surface area of a hollow sphere of a given diameter.
Diameter of the sphere (d) = 7 m
So, surface area of the sphere = `4 pi (d/2)^2`
`=4(22/7)(7/2)^2`
`=(22/7)(3.5)^2`
=154 m2
Therefore, the area available for the motorcyclist for riding is 154 m2 .
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