Transcript Slide 1

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First we need to find he length of each side by
counting the squares.
8 cm
6 cm
6 cm
The distance
around the
outside of a shape
is called the
perimeter.
8 cm
The perimeter of the shape is 8 + 6 + 8 + 6 = 28cm.
18cm
18cm
What is the
perimeter of
each of these
shapes?
22cm
18cm
26cm
Now find the
perimeter of
these shapes.
5cm
3cm
3cm
4cm
3cm
7cm
3cm
7cm
3cm
3cm
Perimeter = 18cm
4cm
3cm
3cm
3cm
3cm
4cm
4cm
3cm
Perimeter = 22cm
Perimeter = 28cm
To find out how much shape is inside we can
count the squares.
The area of a
shape is the
amount of space
inside it.
The area of the shape is 18cm2.
12cm2
What is the area of
each of these
shapes? Your teacher
will give you copy of
the worksheet.
26cm2
26cm2
This is an irregular
shape. This
means that the
sides aren’t
straight.
To find the area of
an irregular shape
you first count the
full squares inside
it.
You then count all
the other squares
which have more
than half the area
covered.
The area of the shape is 60cm2.
24cm2
25cm2
What is the area of
each of these
shapes? Your teacher
will give you copy of
the worksheet.
35cm2
22cm2
The rectangle is made of 6 rows of 8 squares.
To work out the number of squares
we times 6 by 8.
Counting each
square can take a
long time. Does
anyone know a
quicker way?
The area of the shape is 48cm2.
18cm2
2
20cm
What is the area of
each of these
shapes? Your teacher
will give you copy of
the worksheet.
30cm2
14cm2
22cm2
We can work out the area of a rectangle
without the grid.
length
width
Area = length x width
Now work out the
area of these
rectangles.
They are not drawn
to scale.
7cm
9cm
2
35cm2
36cm
5cm
20cm2
5cm
12.5cm
4cm
2cm
25cm2
4cm
Total area = 40 + 32 = 72 cm2
4cm
2cm
10cm
4cm
Area =
4 x 10
40cm
Area =
4x8
2
32cm2
8cm
A shape that is
made from other
shapes is known
as a composite
shape.
8cm
To find the area of
this shape we
have to split it up
into two
rectangles.
5cm
2cm
4cm
9cm
5cm
2cm
4cm
2cm
11cm
5cm
4cm
3cm
3cm
Find the area and
perimeter of each of
these shapes? Your
teacher will give you
copy of the
worksheet.
5cm
4cm
3cm
6cm
4cm
7cm
7cm
6cm
11cm
5cm
2cm
9cm
Area =
5x9
45cm
Area =
4x5
4cm
5cm
2
20cm2
4cm
2cm
5cm
2
Total area = 45 + 20 = 65 cm
Perimeter = 36 cm
2
Total area = 10 + 36 = 46 cm
Perimeter = 34 cm
2cm
Area =
2x5
10cm2
11cm
5cm
4cm
Area =
6x6
36cm2
6cm
6cm
Total area = 28 + 16 + 21 = 65 cm
2
Perimeter = 42 cm
Area =
4x7
28cm2
Area =
4x4
2
16cm
4cm
3cm
3cm
3cm
4cm
7cm
7cm
11cm
There is
another way of
doing this
question.
Area =
3x7
21cm2
2
Total area = 77 – 12 = 65 cm
Perimeter = 42 cm
Area =
3 x 4 12cm2
4cm
3cm
3cm
3cm
4cm
7cm
7cm
Area =
7 x 11
2
77cm
11cm
ACTIVITY :
Each student got a partner, a meter scale, and a piece of
chalk. They took turns laying on the sidewalk and drawing a
rectangle around their partner. Then they measured each side,
recorded the measurement, and then added up the sides to find
the perimeter. The students will walked around and looked at
everyone else's rectangle.
*Peoms to learn and understand area and perimeter
effectively
Perimeter, perimeter
Goes around and round
Add up all the sides and then you write your answer down
Area, area
Through out the whole middle
For rectangles, it's base times height
And your answer will always be right
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5cm
2cm
2cm
4cm
9cm
5cm
5cm
4cm
11cm
2cm
4cm
5cm
6cm
4cm
3cm
3cm
7cm
4cm
11cm
6cm
3cm
7cm
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Review
Name:____________________
What is the area of the moon?
_____________________cm2
What is the area of the rectangle?
_____________________cm2
What is the perimeter of the rectangle?
_____________________cm
What is the area of the house?
_____________________cm2
4cm
8cm
4cm
What is the area of the compound shape?
2cm
_____________________cm2
4cm
What is the perimeter of the compound shape?
_____________________cm
6cm