Calculating Circle Measurements: Radius, Diameter, and Circumference

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

• Radius

• Circumference

• Diameter

• Area

If the diameter of a circle is 8 meters, what is the radius?

• 2 meters

• 4 meters

• 8 meters

• 16 meters

If the radius of a circle is 4 meters, what would be the diameter?

• 16 meters

• 4 meters

• 8 meters

• 2 meters

Which formula is used to calculate the circumference if the diameter is known?

• C = πd

• C = 2πr

• C = r/π

• C = d/π

What is the value of π used in the calculations?

• 22/7

• 3.14

• 3

• 2.14

How do you calculate the diameter if the circumference is given as 78.5 cm?

• Divide by π

• Divide by 2π

• Multiply by 2π

• Multiply by π

What is the circumference of a circle with a diameter of 20 cm using π = 3.14?

• 62.8 cm

• 94.2 cm

• 31.4 cm

• 125.6 cm

If the circumference of a circle is 94.2 cm, what is the radius?

• 15 cm

• 30 cm

• 47.1 cm

• 7.5 cm

Using the formula C = 2πr, what is the circumference for a radius of 12 cm?

• 37.68 cm

• 24 cm

• 75.36 cm

• 150.72 cm

What is the correct step to isolate the diameter in the equation C = πd?

• Subtract π from both sides

• Multiply both sides by π

• Divide both sides by π

• Add π to both sides