Circumference

Question

`A person six feet tall walks around the earth . How many feet farther does the top of this person's head travel then the bottoms of his feet? 

 

In terms of pi

Answer 1

Let the radius of the earth be R. Thus, the circle the head travels has radius R+6.

 

Circumference of earth = 2πR

 

Distance the head travels = 2π(R+6) = 2πR + 12π

 

Finding the difference,

 

(2πR + 12π) - 2πR = 12π

 

So the answer is 12π feet