How do you calculate the area of a circle?

How do you calculate the area of a circle?

• A. Pi x Radius Squared
• B. 3.14 x Radius
• C. Pi x Diameter
• D. 3.14 x Radius Squared

Answer: (D)

The area of a circle depends on the radius and grows with the square of the radius. The exact formula is A = π r^2. If you use the common decimal for π, 3.14, you get A ≈ 3.14 × r^2. That matches the given option, which uses 3.14 times the radius squared. The other options don’t fit: using Pi times Radius is missing the squared term, so it isn’t the correct area formula; using Pi times Diameter would require adjusting for the relationship between diameter and radius and does not simplify to the area formula; and Pi times Radius Squared is correct in exact form, but the option with 3.14 is the standard numeric form often used in problems.

The area of a circle depends on the radius and grows with the square of the radius. The exact formula is A = π r^2. If you use the common decimal for π, 3.14, you get A ≈ 3.14 × r^2. That matches the given option, which uses 3.14 times the radius squared.

The other options don’t fit: using Pi times Radius is missing the squared term, so it isn’t the correct area formula; using Pi times Diameter would require adjusting for the relationship between diameter and radius and does not simplify to the area formula; and Pi times Radius Squared is correct in exact form, but the option with 3.14 is the standard numeric form often used in problems.