Calculating the Circumference of a Circle

The video tutorial explains how to calculate the circumference of a circle using two formulas: one with the diameter (C = πD) and another with the radius (C = 2πR). It provides a step-by-step example where the radius is given, and the diameter is calculated by doubling the radius. The diameter is then used in the formula C = πD to find the circumference, demonstrating the process with a specific numerical example.

What is the formula to calculate the circumference if you know the diameter of the circle?

• C = 2πR

• C = πD

• C = D/π

• C = R/2

If the radius of a circle is 5 inches, what is the diameter?

• 10 inches

• 2.5 inches

• 20 inches

• 5 inches

Using the formula C = 2πR, what is the circumference if the radius is 3 inches?

• Approximately 18.84 inches

• 6 inches

• 9 inches

• 12 inches

In the example given, what is the diameter of the circle when the radius is 4 inches?

• 4 inches

• 8 inches

• 12 inches

• 16 inches

What is the final calculated circumference of the circle in the example?

• 12.7 inches

• 25.5 inches

• 8 inches

• 50 inches