What is the area in square feet of a circular area with a diameter of 20 feet?

To determine the area of a circular area, the formula used is A = πr², where A represents the area and r is the radius of the circle.

In this case, the diameter of the circular area is given as 20 feet. The radius is half of the diameter, so we calculate the radius as follows:

Radius (r) = Diameter / 2 = 20 feet / 2 = 10 feet.

Now, substituting the radius into the area formula:

A = π(10 feet)²

A = π(100 square feet)

A ≈ 3.14 × 100 square feet

A ≈ 314 square feet.

Thus, the area of the circular area with a diameter of 20 feet is approximately 314 square feet, making this answer the correct choice.