Question

The image below shows a parking lot support pole. The pole is cylinder-shaped with a spherical top. All sides, except for the bottom, will be painted. How much surface area is going to be painted?

Answer 1

Solution:

Given:

Since the bottom of the cylinder will not be painted and the top is spherical.

The top is a hemisphere. Hence, the surface area to be painted will be;

$\begin{gathered} A=2\pi rh+2\pi r^2 \\ \\ where; \\ r=10in \\ h=26in \end{gathered}$

Hence,

$\begin{gathered} A=(2\times\pi\times10\times26)+(2\times\pi\times10^2) \\ A=520\pi+200\pi \\ A=720\pi\text{ sq in} \end{gathered}$

Therfore, the surface area to be painted is ;

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