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

To mathematically calculate the special number "pi" you need the __________________________.  

• circumference  &  the diameter 
• diameter  &  the radius 
• any two parts of the circle 

Mathematical Equivalence

ON

What is the the circumference of the following circle?

• 1.32

• 0.69

• 7.89

• 9.42

What Formula is this?

• Area of Triangle

• Perimeter of Circle

• Circumference of Circle

• Area of Circle

Find the circumference of a circle with a diameter of 3.6

• 5.652

• 11.304

• 10.1736

• 5.0868

If my radius is 2 yd what is the circumference?

• 4 yd

• 1 yd

• 12.56 yd

What is the circumference of a circle with a diameter of 9?

• 254.34

• 28.26

• 9.42

• 18.84

What is the circumference of a circle with a radius of 21 cm?

• 131.88 cm
• 121.99 cm
• 111.89 cm
• 141.89 cm

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