Circumference and Areas of a Circle

What is the formula to calculate the circumference of a circle?

• C = Pi * d

• C = Pi * r

• C = 2 * Pi * r

• C = Pi * r^2

What does 'Pi times diameter' calculate in relation to a circle?

• Radius

• Circumference

• Diameter

• Area

What does squaring a number mean?

• Adding it to itself

• Multiplying it by itself

• Multiplying it by 2

• Dividing it by itself

What common mistake do students make when learning to find the area of a circle?

• Using the diameter instead of the radius

• Forgetting to use Pi in the calculation

• Confusing radius with diameter

• Multiplying the radius by 2 instead of squaring it

How do you calculate the area of a circle?

• A = Pi * r

• A = 2 * Pi * r

• A = Pi * d^2

• A = Pi * r^2

What is the relationship between the diameter and the radius of a circle?

• Radius is half the diameter

• Diameter is half the radius

• Radius is double the diameter

• Diameter is double the radius

What is the diameter of a circle if its radius is 8 meters?

• 32 meters

• 16 meters

• 8 meters

• 4 meters

What is the circumference of a circle with a diameter of 16 meters?

• 25.12 meters

• 50.24 meters

• 100.48 meters

• 75.36 meters

What is the area of a circle with a radius of 8 meters?

• 25.12 square meters

• 50.24 square meters

• 100.48 square meters

• 200.96 square meters

How does squaring the radius affect the units of the answer when calculating area?

• It has no effect on the units

• It becomes a 3-dimensional quantity

• It becomes a 2-dimensional quantity

• It remains a 1-dimensional quantity