Answer:
The perimeter of the track is the two circumferences of the semicircles (when combined, they form one circle, so we can just find the circumference of the circle) added to the lengths of the rectangle (160 meters).
To find the circumference of the circle, we need to know the diameter.
Circumference of a circle: dπ or 2rπ, where d represents diameter and r represents radius
The diameter of the circle happens to be the same as the width of the rectangle. We know that the area of a rectangle is found by multiplying its length by its width. We know that the area is 14400 and that its length is 160.
Width: area divided by length
14400160=90
The diameter of the circle and the width of the rectangle is 90 meters.
Circumference:
90⋅π=90π→ If you are using an approximation such as 3.14 for π, multiply that by 90
Add 160⋅2 to the circumference since the lengths of the rectangle are also part of the perimeter.
160⋅2=320
90π+320
Answer link