Circumference and Area of Circles

What is the formula to calculate the circumference of a circle using its radius?

• C = 2πr

• C = πd

• C = πr²

• C = 2πd

If a circle has a radius of 8 cm, what is its area?

• 201.06 cm²

• 50.24 cm²

• 100.53 cm²

• 150.72 cm²

How can the diameter of a circle be found from its circumference?

• Divide the circumference by π

• Multiply the circumference by π

• Square the circumference

• Subtract π from the circumference

What is the relationship between the circumference and the area of a circle?

• c = 2√(πA)

• c = πA

• c = A/π

• c = 2πA

Which of the following units can be used to measure the circumference and area of circles?

• Centimeters

• Liters

• Kilograms

• Seconds