Question

A solid metal cube with an edge length of 9 inches is melted down and reshaped into a sphere. Which of the following is the surface area of the sphere to the nearest tenth of an inch?
A. 90.5 square inches
B. 254.5 square inches
C. 391.7 square inches
A. 574.8 square inches

Answer 1

Answer:

U6 L6: SA & Volume of Spheres Practice Test

1.  A

2. A

3. B

4. B

5. C

6. B

7. B

8. B

9. A

10. D

Source: https://quizlet.com/289419213/surface-areas-and-volumes-of-spheres-practice-u6-l6-connexus-flash-cards/

Answer 2

The solution would be like this for this specific problem:

729 = 4*pi * r^3/3
Multiply both sides by 3   2185 = 4*pi*r3   Divide both sides by 4 pi.   173.9649681528662 = r3

r = 5.58239548   A = 4 pi r^2   A = 4 * 3.14 * 5.582395482
A = 391.7 square inches

 

 

The surface area of the sphere to the nearest tenth of an inch is 391.7 square inches.