If a circle has a radius of 5, what is its area? (Use π ≈ 3.14)

If a circle has a radius of 5, what is its area? (Use π ≈ 3.14)

• A. 78.5 square units
• B. 39.25 square units
• C. 62.8 square units
• D. 157 square units

Answer: (A)

This question tests the area of a circle, which is calculated with area = πr^2. With a radius of 5, the area is π × 5^2 = π × 25 ≈ 3.14 × 25 = 78.5 square units. That matches the given value of 78.5. The other numbers would come from different radii (or misapplying the formula), for example 62.8 would be π × 20 (radius ≈ 4.47), and 157 would be π × 50 (radius ≈ 7.07).

This question tests the area of a circle, which is calculated with area = πr^2. With a radius of 5, the area is π × 5^2 = π × 25 ≈ 3.14 × 25 = 78.5 square units. That matches the given value of 78.5. The other numbers would come from different radii (or misapplying the formula), for example 62.8 would be π × 20 (radius ≈ 4.47), and 157 would be π × 50 (radius ≈ 7.07).