The surface area of a sphere is four times the product of π and the square of the radius of the sphere.
What is the surface area of the sphere in terms of π ?
What are you given?
In sphere problems, make it a habit to note whether you are given the radius or the diameter. In this case, you are given the diameter.
The diameter is 10 m, so the radius is
The surface area is
You can use spheres to approximate the surface areas of real-world objects.
Geography Earth's equator is about 24,902 mi long. What is the approximate surface area of Earth? Round to the nearest thousand square miles.
How can you use the length of Earth's equator?
Earth's equator is a great circle that divides Earth into two hemispheres. Its length is Earth's circumference. Use it to find Earth's radius.
Step 1 Find the radius of Earth.
Step 2 Use the radius to find the surface area of Earth.
The surface area of Earth is about