Question

You have been asked to design a circular practice running track for your school’s track team. The track will have one lane that have a width of 2 meters and a circular interior center with a diameter of 8 meters .

How much grass turf should your principal purchase for the center circular area of the running track?

How much asphalt will be needed to pave the running lane?

Answer 1

50.2655 m2 of grass turf to the interior center area.

62.8319 m2 of asphalt to the running lane.

Explanation:

If the diameter of the interior center is 8 meters, its radius is 8/2 = 4 meters.

So, the area of the interior center is:

Area = pi * r^2 = pi * 4^2 = 50.2655 m2

It will be needed 50.2655 m2 of grass turf to the interior center area.

To find the area of the running lane (for the asphalt), we just need to subtract the area of a circle with 6 meters of radius (4 m from the interior circle plus 2 m from the width of the lane) from the area of the interior circle (radius = 4):

Area of lane = pi * 6^2 - pi * 4^2 = 62.8319 m2

It will be needed 62.8319 m2 of asphalt to the running lane.