Circumference and Pi Calculations

This video tutorial explains the concept of the circumference of a circle, comparing it to the perimeter. It introduces two equivalent formulas for calculating circumference: one using the radius and the other using the diameter. The video demonstrates these formulas through two examples, highlighting the use of the pi button on calculators for more accurate results. The tutorial emphasizes the importance of understanding both exact and approximate values of pi.

What is the term used to describe the distance around a circle?

• Circumference

• Radius

• Diameter

• Area

Which formula can be used to calculate the circumference of a circle using the radius?

• C = pi * d

• C = 2 * pi * r

• C = pi * r^2

• C = 2 * d

How is the mathematical constant pi defined?

• The radius of a circle divided by its circumference

• The diameter of a circle divided by its radius

• The circumference of a circle divided by its diameter

• The area of a circle divided by its radius

In the first example, what is the exact circumference of a circle with a radius of 4 inches?

• 8 pi inches

• 4 pi inches

• 16 pi inches

• 2 pi inches

What is the approximate circumference of a circle with a radius of 4 inches using the pi button?

• 24.00 inches

• 25.13 inches

• 26.00 inches

• 25.12 inches

In the second example, what is the exact circumference of a circle with a diameter of 12.44 meters?

• 12.44 pi meters

• 15.00 pi meters

• 24.88 pi meters

• 6.22 pi meters

What is the approximate circumference of a circle with a diameter of 12.44 meters using the pi button?

• 40.00 meters

• 39.08 meters

• 38.00 meters

• 39.06 meters

Why is using the pi button on a calculator more accurate than using 3.14?

• It rounds pi to the nearest whole number

• It uses pi as 3.00

• It uses a more precise value of pi

• It uses pi as 3.50

What should you do if your instructions specify using 3.14 for pi?

• Use the pi button on the calculator

• Ignore the instructions

• Use 3.14 as the value for pi

• Use 22/7 as the value for pi

What is the importance of using accurate values for pi in calculations?

• It provides more precise results

• It ensures the calculations are faster

• It reduces the number of steps

• It makes the calculations easier