A circle has a radius of 5 cm. What is its area? Use π ≈ 3.1416.

A circle has a radius of 5 cm. What is its area? Use π ≈ 3.1416.

• A. 78.54 cm^2
• B. 50 cm^2
• C. 31.4 cm^2
• D. 25π cm^2

Answer: (A)

Area of a circle is π times the radius squared. With a radius of 5 cm, that’s π × 5^2 = 25π cm^2. Using π ≈ 3.1416, 25π ≈ 25 × 3.1416 = 78.54 cm^2. So the area is about 78.54 square centimeters. The decimal 78.54 cm^2 matches the instruction to use the approximate π, making it the best choice. The exact form 25π cm^2 is equal to this value when π is taken as 3.1416, but the decimal form reflects the given approximation.

Area of a circle is π times the radius squared. With a radius of 5 cm, that’s π × 5^2 = 25π cm^2. Using π ≈ 3.1416, 25π ≈ 25 × 3.1416 = 78.54 cm^2. So the area is about 78.54 square centimeters. The decimal 78.54 cm^2 matches the instruction to use the approximate π, making it the best choice. The exact form 25π cm^2 is equal to this value when π is taken as 3.1416, but the decimal form reflects the given approximation.