Circumference of a Circle

What is the circumference of a pizza with a 10-inch diameter?

• 31.40

• 28.26

• 25.12

• 18.86

In words, describe this formula

• The area of a circle is equal to pi times the radius squared

• The circumference of a circle is equal to the pi times the diameter.

• The circumference of a circle is equal to pi times the radius squared

• The area of a circle is equal to pi times the diameter

Find Circumference.

• 87.92 cm

• 43.96 cm

• 21.98 cm

• 3.14 cm

Find the circumference of a circle with a radius of 12.5 mm .

• 37.68mm

• 18.84mm

• 78.5mm

• none of the above

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

A circle has a diameter of 17 inches. What is the circumference?

• 106.76 inches

• 53.38 inches

• 907.46 inches

• 34 inches

Daniel wants to buy cookies for her friend. The radius of a cookie is 5 inches. What is the cookie’s circumference?

• 10 in

• 2.5 in

• 15.7 in

• 31.4 in 

What is this symbol called?

• pi

• sigma

• radius

• omega

What is the approximate numerical value of this sign?

• 3.11

• 3.14

• 4.13

• 6.28

What is the diameter?

• 6.5

• 15

• 26

• 78