Sure! Here are some practice problems to help you find the surface area of spheres:
1. Find the surface area of a sphere with a radius of 5 cm.
Solution: The formula for the surface area of a sphere is A = 4πr^2.
Plugging in the given radius, we have A = 4π(5^2) = 4π(25) = 100π cm^2.
2. Find the surface area of a sphere with a diameter of 10 inches.
Solution: The radius of the sphere is half of the diameter, so the radius is 10/2 = 5 inches.
Using the formula A = 4πr^2, we have A = 4π(5^2) = 4π(25) = 100π inches^2.
3. Find the surface area of a sphere with a radius of 8 cm.
Solution: The formula A = 4πr^2 gives us A = 4π(8^2) = 4π(64) = 256π cm^2.
4. Find the surface area of a sphere with a diameter of 14 inches.
Solution: The radius is half of the diameter, so the radius is 14/2 = 7 inches.
Using the formula A = 4πr^2, we have A = 4π(7^2) = 4π(49) = 196π inches^2.
Remember to always use the formula A = 4πr^2 to find the surface area of a sphere, where r represents the radius.
surface area of spheres practice
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