vocabulary
Radius
distance from the center of a circle to its ede
How do you find the radius?
Diameter divided by 2
diameter is 5 inches, what is the circumference?
15.7 inches
radius is 3 ft, what is the area?
28.26 ft2
The distance from one edge to another of a circular pool is 6 ft, what is the circumference of the pool?
18.84 ft
Diameter
the distance from one edge of the circle to the other, crossing through the center
How do you find the diameter?
Radius x 2
diameter is 10 cm, what is the circumference?
31.4 cm
radius is 8 mi, what is the area?
200.96 mi2
The radius of a circular garden is 5 ft, calculate how much space the entire garden covers.
78.5 ft2
Area
space inside of a circle
Circumference Formula
radius is 4 ft, what is the circumference?
25.12 ft
diameter is 8 cm, what is the area?
50.25 cm2
Circumference
the distance around a circle
radius squared x pi
radius is 13 yd, what is the circumference?
81.64 yd
diameter is 38 m, what is the area?
1,133.54 m2
Where does pi come from?
ratio of a circle's circumference to its diameter. we googled measurements of objects and calculated this!
The circumference is 18.84 in, what is the circle's diameter?
6 inches
The area of a circle is 254.34 cm2, what is the circle's diameter?
4.5 cm