Circles

Working Backwords

100

how do you get the radious from the circumfrence 

r=c/pi/2

200

How do you get the diamertor from the cercumfrence?

d=c/pi

300

83/pi=?

53 (rounded)

400

Karen LOVES apple pie, she made the circumfrence 110cm but she needs to split it in to half to share with one of her friends what is the diamertor?

35cm

500

Bethany's circle has a circumfrence of 103.50cm. She needs the diamator, what is it?

33 (32.96)cm

circumfernce

100

If the diameter of a pie is 15in what would the circumference would be?

47in(rounded)

200

If the circumfernce is 30km what would be the radius?

19km(rounded)

300

What are the equations for circumfernce

2piR or piR

400

If the radius is 65cm then what is the circumference?

408cm (rounded)

500

R=1,110cm C=?cm

6981cm (rounded)

area

100

If the radius is 2cm what is the area?

13²cm (rounded)

200

THe diameter is 6mm what is the area?

28²mm (rounded)

300

If the diameter is 22km what is the area?

380²cm(rounded)

400

Sia has the diameter of the circle which is 60cm, but she needs help to get the area. What is it?

2827^2cm(rounded)

500

R=65 A=?

13273² (rounded)

radius

100

How do you get the radius?

C/pi/2

200

If the circumfernce is 20 what is the radius?

13 (rounded)

300

Crissy has a diamertor of 300cm what si the radius?

150cm

400

C=200 R=?

127 (rounded)

500

Joseph has a circumfrence of 35in and abigail has a circumfrence of 35.5in. What is the radius AND the area. Witch circle is bigger?

Joseph's radius is 22in(rounded) and his area is and 1559.48in 

Abigail's has a radius of 26.6 and an area of 2222.86in   

Abigails is bigger

Key Terms

100

What is radius?

A line taht goes from the center of the circle to the inner edge of the circle.

200

What is diameter?

Diameter is a line that goes though the middle of the circle and that goes from side to side.

300

What is circumfrence

A circumefence is the outside distance of a circle's edge

400

What is erea?

Area is the whole inside of the circle.