A training field is formed by joining a rectangle and two semicircles. The rectangle is 81 meters long and 50 meters wide. Find the area of the training field and use the value of 3.14 for pi.

Answer 1

Hi! I visualize the training field looking similar to this shape:

The area of the rectangle is length * width, so:

81 * 50 = 4050

The two semi-circles are equivalent to one circle with a radius of 25.

The area of a circle is pi * r², so:

pi * 25² =  3.14 * 625 = 1962.5

4050 + 1962.5 = 6012.5

Answer 2

The total area is the sum of the areas of the semi-circles plus the area of the rectangle.

The sum of the areas of the semi-circles is just the area of a circle whose radius is 25, i.e., pi*25² = 625*pi

The area of the rectangle is length*width = 81*50 = 1650

Using pi = 3.14,

1650 + 625*pi = 3612.5 sq meters