Sphere Surface Area Math Example 3

Follow the full solution, then compare it with the other examples linked below.

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Find the surface area of a sphere with diameter 10 cm.

1
Step 1: Find the radius from the diameter: $r = \frac{d}{2} = \frac{10}{2} = 5$ cm.
2
Step 2: Apply the surface area formula: $SA = 4\pi r^2 = 4\pi(5)^2 = 4\pi(25) = 100\pi$ .
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Step 3: Compute the numerical value: $SA = 100\pi \approx 314.16$ cm².

Answer

SA = 100\pi \approx 314.16

cm²

When given a diameter, always halve it to get the radius before substituting into

SA = 4\pi r^2

. The surface area of a sphere grows with the square of the radius, so doubling the radius quadruples the surface area.

About Sphere Surface Area

The total area covering the curved outer surface of a sphere, given by the formula

S = 4\pi r^2

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