Florida connection academy surface area of spheres practice

Answer 1

Sure! Here are some practice questions for finding the surface area of spheres:

1) Find the surface area of a sphere with a radius of 5 inches.

2) The surface area of a sphere is 201.06 square centimeters. Find the radius of the sphere.

3) A sphere has a surface area of 4π square meters. What is the radius of the sphere?

4) Find the surface area of a sphere with a diameter of 12 centimeters.

5) The surface area of a sphere is 201.06 square inches. Find the diameter of the sphere.

Solution:

1) The formula for the surface area of a sphere is A = 4πr². Substituting the given value, we have A = 4π(5²) = 4π(25) = 100π square inches.

2) Given A = 201.06 square centimeters, we can use the formula A = 4πr² to find the radius. Rearranging the formula, we have r =√(A/4π) = √(201.06/4π) ≈ 5 centimeters.

3) Given A = 4π square meters, we can use the formula A = 4πr² to find the radius. Rearranging the formula, we have r =√(A/4π) = √(4π/4π) = 1 meter.

4) The formula for the surface area of a sphere is A = 4πr². The diameter can be calculated as d = 2r. Given d = 12 centimeters, we have r = 12/2 = 6 centimeters. Substituting this value into the surface area formula, we have A = 4π(6²) = 4π(36) = 144π square centimeters.

5) Given A = 201.06 square inches, we can use the formula A = 4πr² to find the diameter. Rearranging the formula, we have d = √(A/π) = √(201.06/π) ≈ 16 inches.

I hope this helps! Let me know if you have any other questions.