Circumference of Circles and Perimeter of Semi Circles

Which expression could be used to find the approximate circumference of the quilt piece?

• 2(pi)16

• 2(pi)8

• 2(8)

• 2(4)

Which best approximates the circumference of the outer ring of this clip?

• 27cm

• 18cm

• 9cm

• 3cm

What is the circumference?

• 48

• 96

• 24

• 18

What is the circumference?

• 36

• 18pi

• 108pi

• 36pi

What is the perimeter of the semi-circle?

• 11 yd

• 17.27 yd

• 34.54 yd

• 28.27 yd

What is the radius?

• 28

• 15

• 26

• 13

The distance around a circle; much like the perimeter of a rectangle.

• perimeter

• diameter

• circumference

• radius

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 perimeter of the semi-circle?

• 11 yd

• 17.27 yd

• 34.54 yd

• 28.27 yd

What is the perimeter of this semi circle? (Use 3.14 = π and round to the nearest tenths place)

• 18.5

• 11.3

• 20.3

• 22.6