area of circle

Question

The outer circumference of a circular road is 314 m and its inner circumference is 282.6m. Find the width of the circular road

Answer 1

Good morning Sam:

 

you are up early doing homework I see!

 

To solve this problem, you need to find the radii of the inner and outer circles.  Then the width of the road is the difference between the 2 radii.

 

Now you know that the circumference (C) of a circle is equal to 2 times PI times Radius:  C = 2 * PI * R

 

Therefore each radius can be calculated by:  R = C / (2 * PI).

 

Width = R₂ - R₁ = (C₂ - C₁) / (2 * PI) = (314 - 282.6) / (2 * PI) = 5.0 meters (approximately, if you take PI = 3.14).

 

Hope this helps.

 

  Jean-Michel