(A) The formula for the surface area of a sphere is $A = 4 \pi r^2$.Given that $A = 7850 \, cm^2$ and $\pi = 3.14$,we substitute these values into the

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(A) The formula for the surface area of a sphere is $A = 4 \pi r^2$.Given that $A = 7850 \, cm^2$ and $\pi = 3.14$,we substitute these values into the formula:$7850 = 4 \times 3.14 \times r^2$$7850 = 12.56 \times r^2$$r^2 = \frac{7850}{12.56}$$r^2 = 625$$r = \sqrt{625} = 25 \, cm$.Therefore,the radius of the sphere is $25 \, cm$.

Class 9 Mathematics Surface Areas and Volumes Mix Examples - Surface Areas and Volumes

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The surface area of a sphere is $7850 \, cm^2$. Find its radius in $cm$. (Use $\pi = 3.14$)

A
$25$
B
$35$
C
$50$
D
$45.5$

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Mix Examples - Surface Areas and Volumes

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The surface area of a sphere is $7850 \, cm^2$. Find its radius in $cm$. (Use $\pi = 3.14$)

Similar Questions

The radius of a cone is $10\, cm$ and the total surface area of a cone is $880\, cm^2$. Find the slant height in $cm$. (Use $\pi = 22/7$)

The surface area of a sphere and the curved surface area of a hemisphere are equal. Find the ratio of their radii.

Find the total surface area of a cone with diameter $6\, cm$ and slant height $11\, cm$. (in $cm^2$)

Find the curved surface area of a cylinder whose height is $35 \, cm$ and radius of the base is $15 \, cm$. (in $cm^2$)

$A$ well,$20 \, m$ deep,is $7 \, m$ in radius. Find the cost of cementing the inner curved surface at the rate of ₹ $15$ per $m^2$. (in ₹)

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