Post on 18-Nov-2014
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TOBY’S LESSON ON......
The distance around the
outside of a shape is called the perimeter.
8 cm
6 cm
8 cm
6 cm
The perimeter of the shape is 8 + 6 + 8 + 6 = 28cm.
First we need to find he length of each side by counting the squares.
18cm18cm
18cm
22cm
26cm
What is the perimeter of each of these
shapes? Your teacher will give you copy of
the worksheet.
Now find the perimeter of these shapes. They are
not drawn to scale.
3cm
3cm
3cm
3cm
3cm
3cm
5cm
7cm7cm
3cm
4cm 4cm
4cm 4cm
3cm 3cm
3cm3cm
Perimeter = 18cm Perimeter = 22cm Perimeter = 28cm
The area of a shape is the
amount of space inside it.
The area of the shape is 18cm2.
To find out how much shape is inside we cancount the squares.
12cm2
26cm2
26cm2
What is the area of each of these
shapes? Your teacher will give you copy of
the worksheet.
This is an irregular shape. This
means that the sides aren’t
straight. To find the area ofan irregular shape you first count the full squares inside
it.
The area of the shape is 60cm2.
You then count all the other squares which have more than half the area
covered.
24cm225cm2
22cm2
35cm2
What is the area of each of these
shapes? Your teacher will give you copy of
the worksheet.
The area of the shape is 48cm2.
The rectangle is made of 6 rows of 8 squares.
To work out the number of squareswe times 6 by 8.
Counting each square can take a long time. Does anyone know a quicker way?
What is the area of each of these
shapes? Your teacher will give you copy of
the worksheet.
20cm2 18cm2
14cm2
30cm2
22cm2
We can work out the area of a rectanglewithout the grid.
length
wid
thArea = length x width
Now work out the area of these rectangles.
They are not drawn to scale.
36cm235cm2
20cm2
25cm24cm
9cm
7cm
5cm
5cm
4cm
2cm
12.5cm
A shape that is made from other shapes is known as a composite
shape.
To find the area of this shape we
have to split it up into two
rectangles.
10cm
8cm
8cm
2cm
4cm
4cmArea =4 x 10
40cm2
Area =4 x 8
32cm2
Total area = 40 + 32 = 72 cm2
Find the area and perimeter of each of these shapes? Your teacher will give you
copy of the worksheet.9cm
5cm
5cm
2cm
4cm
5cm
4cm
2cm
11cm
7cm
4cm
3cm 3cm
3cm
7cm
6cm
6cm
11cm
2cm
4cm
5cm
4cm
9cm
5cm
5cm
2cm
4cm
5cm
4cm
2cm
Area =5 x 9
45cm2
Area =4 x 5
20cm2
Total area = 45 + 20 = 65 cm2
Perimeter = 36 cm
6cm
6cm
11cm
2cm
4cm
5cmArea =2 x 5
10cm2 Area =6 x 6
36cm2
Total area = 10 + 36 = 46 cm2
Perimeter = 34 cm
11cm
7cm
4cm
3cm 3cm
3cm
7cm
Total area = 28 + 16 + 21 = 65 cm2
Perimeter = 42 cm
Area =4 x 7
Area =4 x 4
4cmArea =3 x 7
21cm2
28cm2 16cm2
There is another way of
doing this question.
11cm
7cm
4cm
3cm 3cm
3cm
7cm
Total area = 77 – 12 = 65 cm2
Perimeter = 42 cm
Area =7 x 11
Area =3 x 4
4cm
77cm2
12cm2
Well done!
I am now off to watch T.V
Keep practicing. There are some worksheets below!Love Toby!
worksheet
one
worksheet
two
worksheet
three
9cm
5cm
5cm
2cm
4cm
5cm
4cm
2cm
11cm
7cm
4cm
3cm 3cm
4cm
3cm
7cm
6cm
6cm
11cm
2cm
4cm
5cm
worksheet
four
Review
What is the area of the moon?
_____________________cm2
What is the area of the rectangle?
_____________________cm2
What is the perimeter of the rectangle?
_____________________cm
Name:____________________
4cm
4cm
4cm
6cm
8cm2cm
What is the area of the compound shape?
_____________________cm2
What is the perimeter of the compound shape?
_____________________cm
What is the area of the house?
_____________________cm2