Question

The radius of Earth is 6,371.0 kilometers and the radius of Earth's Moon is 1,737.5 kilometers. What is the approximate difference in the circumferences, in kilometers, of Earth and Earth's Moon? Round your answer to the nearest tenth of a kilometer.

Answer 1

We calculate for the circumferences of Earth and moon by using the equation,

C = 2πr

For Earth,

C = 2π(6371 km) = 40030.2 km

For Moon,

C = 2π(1737.5 km) = 10917.0 km

The difference between the two circumferences is 29113.2 km approximately.

Answer 2

Explanation:

Circumference of a circle is expressed as;

C = 2πr

r is the radius

Given

radius of Earth r1 = 6,371.0 kilometers

the radius of Earth's Moon r2 = 1,737.5 kilometers

The difference in their circumference will be expressed as;

C = 2π(r1-r2)

C = 2π(6371.0-1737.5)

C = 2π(4633.5)

C = 2(3.14(4633.5))

C = 29,098.38km

C = 29,098.4

Hence the difference in their circumference to the nearest km is 29,098.4km