How to find the Area of this unusual shape

45

55

22

20

This shape is actually 2 rectangles

45

55

22

20

So we need to find the area of each rectangle

45

55

22

20

The blue rectangle is 45 wide by ? long

45

55

22

20

?Remember that rectangles have the two opposites sides equal.

We to have find out ?

45

55

22

20

?So that is 55 - 20

35

- the width of the blue rectangle.

So the Area of the blue rectangle is 45 X 35 which is:

45

55

22

20

1575

So now we only have to find out the Area of the pink rectangle and add it to the blue rectangle

45

55

22

20

1575

We know the pink rectangle is 22 long by 20 wide so all we have to do is multiply the two numbers.

45

55

22

20

X = 4401575

So now we have the Area of both rectangles and we need to add them together

1575

440

So the Area of our unusual shape is

45

55

22

20

1575

440

+ = 2015

Now try these other shapes by clicking on them

15

20

36

8 10

24

10

8

22

13

Practical Application 1

Practical Application 2

Practical Application 3

A rectangle and a triangle20

15

36

Remember the area of a triangle is length X breadth

divided by 2.

A = l X b2

Click here to return to

try the other

shapesClick

here to check

answer

The formula for the Area of a circle is:A = πr2

8 10

What is the area of the blue part of the donut

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try the other

shapes

Click here to check

answer

108

So that is 2 circles

Confused click on this picture if you need

helpClick here to return to

try the other

shapes

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answer

The formula for the Area of a circle is: A = πr2

108

So you have to take away the area of the small circle from the area of the big one.

But first find out the radius of the larger circle which is 10 + the radius of the smaller circle (8)

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try the other

shapesClick here to check

answer

So add the area of the three rectangles

24

10

8

22

13

orFind the Area of the large

rectangle and take away the Area of the smaller inside one.

24

2210

13

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try the other

shapes

Click here to check

answer

How much will it cost to carpet the lounge room and hallway of this house at $55 per sq.m.

5m2m

1m

3.5m

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shapes

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answer

How much will it cost to tile the kitchen and dining room of this house at $68 per sq.m.

5m2m

1m

Kitchen Dining Room

The kitchen is 4m by 2.4m

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try the other

shapes

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answer

Here are the four walls of a bedroom – How much would it cost to paint them at $3.50 per Sq. M.

4.5m 4.5m

3.2m 3.2m

Door

Window

Window2.5m

2.5m 2.5m

2.5m

1m

1.8m

1.5m

1.5m

1.3m

1.7m

Remember we don’t want to paint the door or windows, so think about how you will do it

Help

Click here to check

answer

How to do it!• Find out the area of the four walls and take

away the area of the door and windows• Then multiply the answer by the amount it

costs to paint 1 sq. m.

• E.g. for wall with door

Area of yellow rectangle = 4.5 X 2.5 -

Area of blue

rectangle = 1 X 1.8

Return to problem

Answers

24

10

8

22

13408 398

8 10

817.14

Click on the answer you have

15

20

36

540420

Practical Application 1

Practical Application 2

$14.85

$1365.20

$4325.00

$1078.00

$1960.00

$2378.75

$1485.80

$43.25

480 528

871.41

300 480

1018.29 201.14

$171.85$33.70 $350.00$117.95Practical

Application 3

Yes that’s right

Sorry that is wrong – check your workings – try again!

15

20

36

8 10

24

10

8

22

13

Practical Application 1

Practical Application 2

Practical Application 3