Section: Mathematical Reasoning

21) A great circle of a sphere lies on its surface and contains its center. What is the circumference of a great circle of a sphere that has a surface area that measures 1,476 square centimeters? 

NOTE: Π (or Pi) equals 3.14. 

1. Approximately 68.1
2. 74.5
3. 86.1
4. 54.7

SA = 4Πr² finds the radius.

4(3.14)r² = 1,476cm²
12.56r² = 1,476cm²
r² = 117.51592356687898
r = 10.840476168825749 (or 10.84)

Place the value of the radius in the circumference formula (C = 2Πr)

C = 2(3.14)(10.84) = 68.0752 or approximately 68.1 (Answer 1).