Exploring the Circumference of a Circle

What is the first step to find the circumference if the area of the circle is known?

• Calculate the diameter

• Find the radius using the area formula

• Multiply the area by pi

• Divide the area by pi

Tags

CCSS.7.G.B.4

What formula is used to calculate the area of a circle?

• Circumference = pi * diameter

• Area = 2 * pi * radius

• Area = pi * radius squared

• Circumference = 2 * pi * radius

Tags

CCSS.7.G.B.4

After dividing the area equation by pi, what equation do we get?

• diameter squared = 36

• radius squared = 36

• radius = 36

• diameter = 36

Tags

CCSS.7.G.B.4

What is the value of the radius derived from the area?

• Radius = 8

• Radius = 7

• Radius = 6

• Radius = 5

Tags

CCSS.7.G.B.4

How do we confirm the radius value when solving the equation r squared = 36?

• By taking the negative square root

• By taking the positive square root

• By dividing by pi

• By multiplying by pi

Tags

CCSS.8.EE.A.2

What formula is used to find the circumference of a circle?

• Circumference = 2 * pi * diameter

• Circumference = pi * radius

• Circumference = 2 * pi * radius

• Circumference = pi * diameter

Tags

CCSS.7.G.B.4

If the radius of the circle is 6, what is the circumference?

• 6pi

• 24pi

• 12pi

• 18pi

Tags

CCSS.7.G.B.4

What is the final step in determining the circumference after finding the radius?

• Divide the radius by 2 and then multiply by pi

• Subtract pi from the radius and multiply by 2

• Add pi to the radius and multiply by 2

• Multiply the radius by 2 and then by pi

Tags

CCSS.7.G.B.4