Circles slide share
- 1. Circumference of a Circle
Calculate the
Circumference
Using the Correct
Formula
2-Oct-13
© Brain-Cells: E.Resources Ltd. All Rights Reserved 24/11/09 www.brain-cells.co.uk
- 2. C = Πd
C = 3.14 X 12
C = 37.68 cm
The circumference of a circle is its perimeter
– the distance all the way around the edge. It
is calculated using the formula:
Diameter = 12 cm
C = Πd
The value Π can never be found
exactly but for most problems
the approximate value 3,14 is
used.
© Brain-Cells: E.Resources Ltd. All Rights Reserved 24/11/09 www.brain-cells.co.uk
- 3. Area of a Circle
Calculate the Area
Using the Correct
Formula
2-Oct-13
© Brain-Cells: E.Resources Ltd. All Rights Reserved 24/11/09 www.brain-cells.co.uk
- 4. The Circle
1. Calculate the area of a circle
RADIUS The distance from
the centre to the edge
DIAMETER The distance
from one side to the other
passing through the centre
Π = 3.14 (approximately)
D = 2 x R and R = D 2
© Brain-Cells: E.Resources Ltd. All Rights Reserved 24/11/09 www.brain-cells.co.uk
- 5. Radius = 6 A = πr2
A = 3.14 x r x r
A = 3.14 x 6 x 6
A = 113.04 cm2
The area of a circle is calculated using the
formula:
© Brain-Cells: E.Resources Ltd. All Rights Reserved 24/11/09 www.brain-cells.co.uk