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To calculate the area of basic compound shapes

Mathematics - 2D Perimeter and Area

Miss Kim

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In this lesson, you will need:

Exercise book or paper

Ruler

Pencil

2

Image credit: Pixabay

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Starter quiz

Recap previous lessons

Calculating area of compound shapes

Independent worksheet

Exit quiz

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Keywords

Area - The amount of space taken up by a 2D shape.

Compound shapes - A compound shape is a more complex shape that is made up of two or more simple shapes.

Rectilinear shapes - A shape that has straight sides and right angles. It can look like two rectangles joined together.

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Recap

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All of these rectangles have the same area.

True

False

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Image credit: Pixabay

3 cm

4 cm

12 cm

1 cm

2 cm

5 cm

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All of these rectangles have the same area.

True

False

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Image credit: Pixabay

12 cm²

10 cm²

12 cm²

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The formula for calculating area is:

Area = length x width

True

False

8

4 x 3 = 12 cm²

3 cm

4 cm

Image credit: Pixabay

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The area of this shape is:

30 cm²

30 cm

36 cm

36 cm²

9

10 cm

3 cm

10 x 3 = 30 cm²

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Area

How would you calculate the area of this shape?

By multiplying the length by width!

7 x 5 = 35 cm²

10

5 cm

7 cm

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Calculating the area of basic compound (rectilinear) shapes

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Warm up

Rectilinear shapes

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18 cm

20 m

4 km

60 mm

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Area of compound shapes

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3 cm

5 cm

7 cm

2 cm

4 cm

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Area of compound shapes

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15 cm²

3 cm

5 cm

7 cm

2 cm

4 cm

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Area of compound shapes

15

15 cm²

3 cm

5 cm

7 cm

2 cm

4 cm

15 cm²

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Area of compound shapes

16

15 cm²

3 cm

5 cm

7 cm

2 cm

4 cm

15 cm²

8 cm²

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Area of compound shapes

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15 cm²

3 cm

5 cm

7 cm

2 cm

4 cm

15 cm²

8 cm²

15 cm² + 8 cm² = 23 cm²

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Split this compound shape and calculate the area.

5 x 2 = 10 m²

3 x 3 = 9 m²

10 m² + 9 m² = 19 m²

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2 m

5 m

3 m

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Split this compound shape and calculate the area.

5 x 2 = 10 km²

3 x 2 = 6 km²

10 km² + 6 km² = 16 km²

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3 km

2 km

5 km

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Now it’s your turn!

Split this compound shape and calculate the area.

6 x 2 = 12 cm²

2 x 2 = 4 cm²

12 cm² + 4 cm² = 16 cm²

20

6 cm

2 cm

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Now it’s your turn!

Split this compound shape and calculate the area.

8 x 4 = 32 m²

6 x 4 = 24 m²

32 m² + 24 m² = 56 m²

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8 m

4 m

6 m

4 m

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Now it’s your turn!

Split this compound shape and calculate the area.

7 x 3 = 21 cm²

9 x 4 = 36 cm²

36 cm² + 21 cm² = 57 cm²

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9 cm

11 cm

4 cm

7 cm

3 cm

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Split this compound shape and calculate the area.

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2 km

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Split this compound shape and calculate the area.

4 x 2 = 8 km²

7 x 2 = 14 km²

2 x 2 = 4 km²

8 m² + 14 km² + 4 km² = 26 km²

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2 km

4 km

7 km

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Now it’s your turn!

Split this compound shape and calculate the area.

7 x 3 = 21 m²

3 x 2 = 6 m²

4 x 3 = 12 m²

21 m² + 6 m² + 12 m² = 39 m²

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7 m

3 m

2 m

3 m

4 m

3 m

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Split this compound shape and calculate the area.

26

7 m

4 m

6 m

11 m

5 m

7 m

4 m

6 m

11 m

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Split this compound shape and calculate the area.

7 x 6 = 42 m²

11 x 4 = 44 m²

42 m² + 44 m² = 86 m²

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7 m

4 m

6 m

11 m

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Now it’s your turn!

Calculate the area of this compound shape.

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5 m

11 m

5 m

Image credit: Pixabay

5 m

11 m

6 m

5 m

9 m

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Now it’s your turn!

Calculate the area of this compound shape.

11 x 5 = 55 m²

5 x 4 = 20 m²

55 + 20 = 75 m²

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5 m

11 m

5 m

4 m

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Independent worksheet

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Pause the video to complete your task

Resume once you’re finished

To calculate and measure perimeter

Copy and complete all questions on the independent worksheet before you continue.

You can draw the shapes in your exercise book.

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Times tables Chart

Note: If you need some assistance with your times tables, you can use a times tables chart.

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Worksheet Answers

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Question 1

Calculate the area of this compound shape.

Look carefully at all the units. Note: not drawn to scale

7 cm

5 cm

11 cm

8 cm

4 cm

8 x 7 = 56 cm²

5 x 4 = 20 cm²

Add the area of each rectangle together.

56 + 20 = 76 cm²

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Question 2

Calculate the area of this compound shape.

Look carefully at all the units. Note: not drawn to scale

11 x 9 = 99 km²

20 x 8 = 160 km²

Add the area of each rectangle together.

160 km² + 99 km² = 259 km²

9 km

8 km

20 km

11 km

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Question 3

Calculate the area of this compound shape.

Look carefully at all the units. Note: not drawn to scale

7 m

12 m

4 m

5 m

5 x 4 = 20 m²

12 x 2 = 24 m²

Add the area of each rectangle together.

20 m² + 20 m² + 24 m² = 64 m²

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Question 4

Calculate the area of this compound shape.

Look carefully at all the units. Note: not drawn to scale

3 x 2 = 6 m²

9 x 3 = 21 m²

5 x 4 = 20 m²

Add the area of each rectangle together.

6 m² + 21 m² + 20 m² = 47 m²

5 m

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Image credit: Pixabay

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