Area
Circumference
Vocabulary (Mostly)
Random
100
What is the formula for area of a circle?
Area = pir^2
100
What are both formulas for circumference of a circle?
Need BOTH
C=2pir or C=pid
100
What is another name for a perimeter of a circle?
The circumference
100
What is the black line called?
Radius
200
What is the area of this circle to the nearest tenth?
A=pir^2
A=49pi=153.9 i n^2
200
What is the circumference of this, to the nearest tenth?
C=pid=8pi=25.1cm
200
What is the red line called?
Diameter
200
If the Radius is 20 ft, what is the diameter?
double, so 40 ft.
300
What is the area of this circle, to the nearest tenth?
the radius = 9 so...
A=pir^2 =9^2pi=81pi=254.5
(254.4 works)
300
What is the circumference, to the nearest tenth, from a circle with a diameter of 51 cm?
C=pid=pi51=160.2 cm
300
If the diameter is 14 cm, what is the radius?
half of it, so 7 cm.
300
What is:
7-2 2/3=
4 1/3
400
What is the radius?
What is the area?
What is the diameter?
radius = 3
area =
pir^2=3^2pi=9pi=28.3 or 28.2
d=6
400
What is the circumference to the nearest tenth, of a circle with a radius of 17 cm?
C=2pir=2pi17=34pi=106.8 cm
or C=pid=pi34=106.8 cm
400
If the diameter of a circle is 18, what is the AREA of the circle? (Draw a picture if this helps)
Radius =
18div2=9
A=pir^2=pi9^2=81pi=254.5 or 254.4
400
Find area:
24 + 12 = 36
500
What is the area in terms of pi?
RADIUS = 6 SO....
A=pir^2=6^2pi=36pi
500
What is the circumference in terms of pi?
DIAMETER = 16 SO... OR
2pir=2pi8=16pi
500
The gardener needs to find the area of this circular garden, what is the area to the nearest tenth?
A=pir^2
radius = 21 div 2 = 10.5
A=pi10.5^2=110.25pi=346.4 or 346.3
500
Find the perimeter
26 cm