Circumference of a Circle

The diameter of a circle is 3 centimeters. What is the circumference?

• 11.5cm2
• 9.42 cm2
• unicorns are awsome
• 45.3 cm2

Radius 6 cm
What is the diameter? 

• 36 cm
• 12 cm
• 6 cm
• 3 cm 

Diameter 32 inches
What is the radius?

• 16 inches
• 64 inches
• 96 inches
  96 inches
• 16 ft 

Radius 4 inches
Find the circumference of the circle. 

• 25.12 in
• 12.56 in
• 50.24 in
• 200.96 in

Diameter 13.5 in
Find the circumference of the circle.

• 84.79 in
• 42.39 in
• 21.195 in
• 572.265 in 

Ray wants to build a fence around his circular garden outside. The garden has a radius of 6 ft. How many feet of fencing does he need?

• 37.68 ft
• 18.84 ft
• 113.04 ft
• 452.16 ft

Other than the formula C=πd what is another formula for circumference of a circle?

• C=2π
• C=2πr
• C=πr²
• C=πd²

Alex has trained his puppy, Popper, to jump through a ring. According to Alex's measurements and calculations, the ring has a diameter of 3.5 feet. What is the ring's circumference (use 3.14 for pi)?

• 11.32 ft
• 12.25 ft
• 10.99 ft
• 8.75 ft

What is the circumference of a circle with a radius of 5 in terms of π ?

• 5 π square units
• 10 π square units
• 25 π square units
• 50 π square units

What is the diameter?

• 6.5
• 15
• 26
• 78