Area
Circumference
Diameter/Radius
Random
Circle Vocabulary
100
What is the formula for the area of a circle?
Pi x r x r
100
What is the formula for circumference of a circle?
Pi x d
100
If you are given the radius, how can you find the diameter?
Multiply radius by two
100
What numerical value is used for pi in the equation for area and circumference of circles?
3.14
100

Distance around a circle (another name for the perimeter of the circle)

Circumference

200
What is the area of a circle with a radius of 15 cm?
706.5 cm
200
What is the circumference of a circle with a diameter of 14.8 cm?
46.5 cm
200
If given the diameter, how can you find the radius?
Divide the diameter by two
200
What is the relationship between the radius and diameter of a circle?
Radius is half the diameter. OR Diameter is two times the radius
200

A point that is equal distance to all points on a circle

Center Point

300
What is the area of circle with radius 39 cm?
1194 cm
300
What is the circumference of a circle with a diameter of 41.3 cm?
129.7 cm
300
If a circle has a radius of 15 cm, what is the diameter?
30 cm
300
Is the exponent, 2, used in the answer for area or circumference of a circle?
Area
300

What starts at the center and goes to any point on the circle?

Radius

400
What is the area of a circle with diameter 24.8 in?
482.8 in
400
What is the circumference of a circle with a radius of 19.7cm?
123.7 cm
400

A circle has a circumference of 62.8 ft, what is the diameter?

20 ft

400
What is the diameter of a circle if the circumference is 78.5 ft?
25 ft
400

A line segment that goes from one point on the circle, through the center, to another point on the circle

Diameter

500
What is the area of a circle with diameter 23.78 in?
443.9 in
500
What is the circumference of a circle with radius 23.25 in?
146 in
500

An iron rod with the length of 10.38ft is bent to form a circle. What is the RADIUS of the circle? Round to the nearest hundredth. 

1.65 ft

500
What are two ways we can write the formula for circumference of a circle?
Pi x d OR Pi x 2 x r
500

What do we call a line segment that goes from one point on the circle to another point on the circle?

Chord

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