What is the area you use for calculating circumference when you know the radius of the circle?
C= 2 x 3.14 x r
What is the area you use for calculating circumference when you know the diameter of the circle?
C= 3.14x D
What does pie equal?
3.14
How is a circle different than other polygon?
It has curves! No straight edges!
With the diameter of 3m, find circumference
9.42 m
With the diameter of 6, find circumference
18.34 m
With the diameter of 156m, find circumference
489.84 m
With the radius of 12m, find circumference
75.36 m
With the radius of 88cm, find circumference
552.64 cm
With the radius of 49 m, find circumference
307.72 m
With the diameter of 156m, find area
19103.76 m^2
With the diameter of 62m, find area
3017.54 m^2
With the diameter of 95m, find area
7084.625 m^2
With the radius of 22 m, find area
1519.76 m^2
With the radius of 1 m, find area
3.14 m^2
In your own words, define radius, diameter, and
circumference. Then explain how a circle’s radius,
diameter, and circumference are mathematically
related.
radius is diameter/2
diameter is 2x radius
circumference is d x 3.14
The diameter of a wheel of a car is 0.55 m. The
car is travelling at 45 km/h. Calculate the number
of revolutions per minute made by the car wheel
when it is travelling. Round your answer to the
nearest full revolution.
26 times
The radius of a circular pond is 8 m. Find circumference AND area
C= 50.25 m
A= 200.96 m^2
The radius of a circular pond is 87 m. Find circumference AND area
C= 5465.36 m
A= 23766.66 m^2
The diameter of a circular pond is 2.68 m. Find circumference AND area
C= 19.7192 m
A= 30.95