Question

The circumference of the Earth is approximately 25,000 miles. Find the diameter of the Earth.

A.) 7,957.8 miles
B.) 7,958.7 miles
C.) 7,958.6 miles
D.) 7,957.7 miles

Answer 1

c=
`\pi d`

25000/
`\pi`
= b

Answer 2

The circumference of a circle is expressed as:

Circumference = 2 x pi x r

where r is the radius of the circle and is equal to half of the diameter.

25000 miles = 2 x 3.14 x r
r = 3980.89 miles
r = 7961. 8 miles

The best answer from the choices is B.