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Which book needs more space?
The Atlas needs more space because it has a bigger surface.
Which shape needs more space?
The yellow one needs more space.
Which object needs more space?
The amount of surface covered by the blackboard is called the
area.
Blackboard Student’s desk
Which shape has the larger area?
Sometimes it is difficult to tell.So what do we need to do?
We can use small squares to cover small objects.
We can use sheets of newspaper to cover larger surfaces.
The area of the shape can be found by ticking the square as each one is counted.
How can we find the area of a shape which has been drawn on squared paper?
Area = _____ square units.
12
Area = _____ square units.
16
Area = _____ square units.
20
Area = _____ square units.
24
Find the area of these shapes.
Different shapes can have same area.
Shapes can be made up of whole squares and half squares.
Two halves make up one whole square.
Letter E has 15 wholewhole squares and 1 halfhalf square.
Area = 15 ½ square units
Letter A has: 14 wholewhole squares 2 halfhalf squares (2 halves make 1 whole square)
Area = 14 + 1 square units = 15 square units
This shape has: 20 wholewhole squares 12 halfhalf squares (2 halves make 1 whole square)
Area = 20 + 6 square units = 26 square units
12 half squares = 6 whole squares
Area = _____ square units.
___ whole squares + ___ half squares 22
20 4
Area = _____ square units.
___ whole squares + ___ half squares 16 6
19
Area of letters and shapes can be found by using the
nailboard.
To take measurements we can use the:
• metre ruler• measuring tape• trundle wheel• ruler
1 square represents 1 cm
Area = _____ square centimetres.
26
1 square represents 1 cm
Area = _____ square centimetres.
26 ___ whole squares + ___ half squares 24 4
1 square represents 1 cm
Area = _____ cm2. 26
Area= 6.5 cm x 4 cm = 26
cm2
length
bre
ad
th
Area = length x breadth
11 cm
7 c
m
Area = length x breadth = 11 cm x 7 cm
= 77 cm2
Length Breadth6cm 5cm5cm 4cm8cm 3cm9cm 4cm6cm 6cm20cm 8cm
30cm2
20cm2
24cm2
36cm2
36cm2
160cm2
Area
1 cm1 c
m
1 m
1 m
Area = 1cm x 1cm =
1cm2
Area = 1m x 1m= 1m2
Large surfaces are measured in m2
Old Trafford Stadium has a length of 150 metres and a width of 50 metres. What is the area of this football ground? 150m
50m
150m
50m
A field is 17m long and 15m wide. What is the area of the field?
17m
15m15m
17m
The diagonal divides the rectangle into 2 equal triangles.
10 cm
6 c
m
= ½ (area of rectangle)
Area of
10 cm
6 c
m
Area of rectangle = 60 cm2
Area of
Area of each triangle = 30 cm2
= ½ (length x breadth)
4 cm
7 c
m
AABB
8 cm5 c
m
CC
6 cm
10 c
m
40 cm40 cm22 30 cm30 cm2228 cm28 cm22
6 cm12 c
m
5 c
m
10 cm
AA
BB
4 cm5 c
mAA
Area of rectangle A = 5cm x 4cm = 20
cm2
Area of rectangle B = 10cm x 7cm = 70
cm2
10 cm7 c
m
BB
6 cm12 c
m
5 c
m10 cm
AA
BB
rectangle A = 20cm2 rectangle B = 70cm2 +
= 90cm2
area
5 cm
2 cm
11 c
m
8 c
m28 cm28 cm22
31 cm31 cm22
55 cm55 cm22
14 cm
22 cm
8
cm
16 c
m
BB
AA
AA
Area of rectangle A = 22cm x 16cm
= 352cm2
8
cm BB
Area of rectangle B = 14cm x 8cm
= 112cm2
14 cm
22 cm
8
cm
16 c
mBB
AA
Area of rectangle A = 352cm2 Area of rectangle B = 112cm2
-
Area of border
= 240cm2
A rectangular pond, 6m long and 4m wide, has a path 1.5m wide all around it. Find the area of this path.
PonPondd
4 m
6 m
1.5 m1.5 m
1.5
m1
.5 m
9m9m
77 mm
77 mm
9m9m
PonPondd
Area of rectangle = 9m x 7m
= 63m2
PonPondd
Area of pond = 6m x 4m
= 24m2
6m6m
44 mm
PonPondd
4 m
6 m
1.5 m1.5 m
1.5
m1
.5 m
9m
7m
Area of rectangle = 63m2 Area of pond
Area of path = 39m2
= 24m2 -
