Finding the Circumference of a Circle

This video tutorial explains how to find the circumference of a circle using the diameter or radius. It introduces the concept of circumference as the boundary of a circle and highlights the importance of the irrational number Pi (π) in these calculations. The video demonstrates that the diameter fits around the circumference π times, leading to the formula π times diameter. It also covers the alternative formula using the radius, which is half the diameter. The tutorial concludes with practice questions for viewers to apply their learning.

What is the circumference of a circle?

• The radius of the circle

• The area inside the circle

• The distance around the edge of the circle

• The diameter of the circle

How many times does the diameter fit around the circumference of a circle?

• Exactly 4 times

• Exactly 3 times

• Exactly 2 times

• Exactly π times

Which formula represents the circumference of a circle using the diameter?

• π times radius

• π times diameter

• 2 times π times radius

• Diameter divided by π

If the radius of a circle is given, how can you calculate the circumference?

• Multiply the radius by 3 and then by π

• Multiply the radius by π and then subtract it

• Multiply the radius by 2 and then by π

• Multiply the radius by π and then double it

What is the alternative formula for calculating the circumference using the radius?

• π times diameter

• Diameter divided by 2

• 2 times π times radius

• π times radius