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SkillsDMC ©
Section 3
Performing calculations
Area
Area is the measurement of the amount of
space covered on a flat surface. Area is usually
expressed as a squared figure and is represented
as a small 2 like
2
. The term squared in maths is
when a figure actually equals what it would if it
was multiplied by itself. It is just another way of
writing it.
For example, 3 metres squared
2
is the same as
3m x 3m.
Calculating the measurement of an area depends
on the shape you are measuring. The following
examples show how to calculate the area of a
square, triangle and circle.
Rectangle or square
Multiply the length by the height to find the area:
Area = Length x Height.
The following is an example is how to calculate
the area of a rectangle.
Area = 8 m x 6 m = 48 m
2
(square metres)
Triangle
Multiply the vertical height by the base and divide
the result by 2: Area = ½ (base x height)
Area = 3 m x 8 m = 24 m
2
(square metres)
24 m ÷ 2 = 12 m
2
(square metres)
Circle
Definitions:
The
circumference
is the distance around a
circle.
The
diameter
is the length of a straight line
passing through the centre of a circle and
connecting two points on the circumference.
Pi
is the circumference of a circle divided
by its diameter and is always the same. It is
approximately 3.142 and is represented by the
Greek letter for P which is π.
The
radius
is the measurement from the centre