What is the circumference of a circle with a radius of 5 units?

What is the circumference of a circle with a radius of 5 units?

• A. 25.0 units
• B. 31.4 units
• C. 15.7 units
• D. 20.0 units

Answer: (B)

The circumference of a circle is calculated using the formula \( C = 2 \pi r \), where \( C \) represents the circumference and \( r \) is the radius of the circle. In this case, the radius is given as 5 units. Plugging the radius into the formula, you get: \[ C = 2 \pi (5) = 10 \pi \] Using an approximate value for \( \pi \) of 3.14, the calculation becomes: \[ C \approx 10 \times 3.14 = 31.4 \text{ units} \] Therefore, the circumference of the circle is approximately 31.4 units. This aligns with the correct answer, which reinforces the understanding of how to apply the formula for circumference given the radius. In this situation, the other answers do not satisfy the calculation based on the established formula and the given radius.

The circumference of a circle is calculated using the formula ( C = 2 \pi r ), where ( C ) represents the circumference and ( r ) is the radius of the circle. In this case, the radius is given as 5 units.

Plugging the radius into the formula, you get:

[

C = 2 \pi (5) = 10 \pi

]

Using an approximate value for ( \pi ) of 3.14, the calculation becomes:

[

C \approx 10 \times 3.14 = 31.4 \text{ units}

]

Therefore, the circumference of the circle is approximately 31.4 units. This aligns with the correct answer, which reinforces the understanding of how to apply the formula for circumference given the radius.

In this situation, the other answers do not satisfy the calculation based on the established formula and the given radius.