Sphere Surface Area Math Example 1

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Example 1

easy
Find the surface area of a sphere with radius 77 cm.

Solution

  1. 1
    Step 1: Recall the surface area formula for a sphere: SA=4ฯ€r2SA = 4\pi r^2.
  2. 2
    Step 2: Substitute r=7r = 7 cm: SA=4ฯ€(7)2=4ฯ€(49)=196ฯ€SA = 4\pi(7)^2 = 4\pi(49) = 196\pi.
  3. 3
    Step 3: Calculate the numerical value: SA=196ฯ€โ‰ˆ615.75SA = 196\pi \approx 615.75 cmยฒ.

Answer

SA=196ฯ€โ‰ˆ615.75SA = 196\pi \approx 615.75 cmยฒ
The surface area formula 4ฯ€r24\pi r^2 gives the total area of the curved surface of a sphere. With radius 7 cm, we compute 4ร—ฯ€ร—49=196ฯ€โ‰ˆ615.754 \times \pi \times 49 = 196\pi \approx 615.75 cmยฒ.

About Sphere Surface Area

The total area covering the curved outer surface of a sphere, given by the formula S=4ฯ€r2S = 4\pi r^2.

Learn more about Sphere Surface Area โ†’

More Sphere Surface Area Examples

Example 2 medium

A sphere has a surface area of [formula] cmยฒ. Find its radius and volume.

Example 3 medium

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

Example 4 easy

A basketball has a diameter of [formula] cm. Find its surface area.

Example 5 hard

Two spheres have radii in the ratio [formula]. Find the ratio of their surface areas. If the smaller

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