Calculate the area of the following quadrant, giving your answer as an exact value in terms of \(\pi\). (2 marks)
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Calculate the area of the following quadrant, giving your answer as an exact value in terms of \(\pi\). (2 marks)
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\(\dfrac{225\pi}{4}\ \text{cm}^2\)
\(\text{Area quadrant}\) | \(=\dfrac{1}{4}\times\pi r^2\) |
\(=\dfrac{1}{4}\times\pi\times 15^2\) | |
\(=\dfrac{225}{4}\pi\) | |
\(=\dfrac{225\pi}{4}\ \text{cm}^2\) |
Calculate the area of the following semi-circle, giving your answer as an exact value in terms of \(\pi\). (2 marks)
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\(1250\pi\ \text{m}^2\)
\(\text{Diameter}=100\ \text{m}\)
\(\therefore\ \text{Radius}=50\ \text{m}\)
\(\text{Area semi-circle}\) | \(=\dfrac{1}{2}\times\pi r^2\) |
\(=\dfrac{1}{2}\times\pi\times 50^2\) | |
\(=1250\pi\ \text{m}^2\) |
Calculate the area of the following semi-circle, giving your answer to 2 decimal places. (2 marks)
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\(0.57\ \text{mm}^2\ (2\ \text{d.p.})\)
\(\text{Diameter}=1.2\ \text{mm}\)
\(\therefore\ \text{Radius}=0.6\ \text{mm}\)
\(\text{Area semi-circle}\) | \(=\dfrac{1}{2}\times\pi r^2\) |
\(=\dfrac{1}{2}\times\pi\times 0.6^2\) | |
\(=0.5654\dots\) | |
\(\approx 0.57\ \text{mm}^2\ (2\ \text{d.p.})\) |
Calculate the area of the following semi-circle, giving your answer to 2 decimal places. (2 marks)
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\(173.18\ \text{m}^2\ (\text{2 d.p.})\)
\(\text{Diameter}=21\ \text{m}\)
\(\therefore\ \text{Radius}=10.5\ \text{m}\)
\(\text{Area semi-circle}\) | \(=\dfrac{1}{2}\times\pi r^2\) |
\(=\dfrac{1}{2}\times\pi\times 10.5^2\) | |
\(=173.1802\dots\) | |
\(\approx 173.18\ \text{m}^2\ (2\ \text{d.p.})\) |
Calculate the area of the following circle, giving your answer as an exact value in terms of \(\pi\). (2 marks)
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\(25\pi\ \text{m}^2\)
\(\text{Diameter}=10\ \text{m}\)
\(\therefore\ \text{Radius}=5\ \text{m}\)
\(\text{Area}\) | \(=\pi r^2\) |
\(=\pi\times 5^2\) | |
\(=25\pi\ \text{m}^2\) |
Calculate the area of the following circle, correct to one decimal place. (2 marks)
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\(422.7\ \text{cm}^2\ (1\ \text{d.p.})\)
\(\text{Diameter}=23.2\ \text{cm}\)
\(\therefore\ \text{Radius}=11.6\ \text{cm}\)
\(\text{Area}\) | \(=\pi r^2\) |
\(=\pi\times 11.6^2\) | |
\(=422.7327\dots\) | |
\(\approx 422.7\ \text{cm}^2\ (1\ \text{d.p.})\) |
Calculate the area of the following circle, correct to one decimal place. (2 marks)
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\(50.3\ \text{m}^2\ (1\ \text{d.p.})\)
\(\text{Area}\) | \(=\pi r^2\) |
\(=\pi\times 4^2\) | |
\(=50.2654\dots\) | |
\(\approx 50.3\ \text{m}^2\ (1\ \text{d.p.})\) |
Calculate the area of the following circle, correct to one decimal place. (2 marks)
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\(514.7\ \text{cm}^2\ (1\ \text{d.p.})\)
\(\text{Area}\) | \(=\pi r^2\) |
\(=\pi\times 12.8^2\) | |
\(=514.7185\dots\) | |
\(\approx 514.7\ \text{cm}^2\ (1\ \text{d.p.})\) |
Calculate the area of the following composite figure in square centimetres (2 marks)
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\(15.5\ \text{cm}^2\)
\(\text{Area}\) | \(=1\times \text{triangles}+1\times\text{trapezium}\) |
\(=\dfrac{1}{2}\times bh +\dfrac{h}{2}(a+b)\) | |
\(=\dfrac{1}{2}\times 5\times 3+\dfrac{2}{2}\times (3+5)\) | |
\(=7.5+8\) | |
\(=15.5\ \text{cm}^2\) |
Calculate the area of the following composite figure in metres squared. (2 marks)
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\(1116\ \text{m}^2\)
\(\text{Area}\) | \(=3\times \text{triangles}+1\times\text{square}\) |
\(=\dfrac{1}{2}\times 24\times 12+\dfrac{1}{2}\times 24\times 9+\dfrac{1}{2}\times 24\times 24+24^2\) | |
\(=144+108+288+576\) | |
\(=1116\ \text{m}^2\) |
Calculate the area of the following composite figure in square centimetres. (2 marks)
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\(182\ \text{cm}^2\)
\(\text{Area}\) | \(=\text{Area triangle 1}+\text{Area triangle 2}\) |
\(=\dfrac{1}{2}\times 14\times 12+\dfrac{1}{2}\times 14\times 14\) | |
\(=84+98\) | |
\(=182\ \text{cm}^2\) |
The triangle below is isosceles.
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a. \(12\ \text{m}\)
b. \(60\ \text{m}^2\)
Calculate the area of the following triangles.
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a. \(87.42\ \text{m}^2\)
b. \(1995\ \text{mm}^2\)
c. \(6650\ \text{m}^2\ \text{or}\ 0.665\ \text{m}^2\)
a. | \(\text{Area}\) | \(=\dfrac{1}{2}\times bh\) |
\(=\dfrac{1}{2}\times 12.4\times 14.1\) | ||
\(=87.42\ \text{m}^2\) |
b. | \(\text{Area}\) | \(=\dfrac{1}{2}\times bh\) |
\(=\dfrac{1}{2}\times 42\times 95\) | ||
\(=1995\ \text{mm}^2\) |
c. | \(\text{Area in (cm)}^2\) | \(=\dfrac{1}{2}\times bh\) |
\(=\dfrac{1}{2}\times 95\times 140\) | ||
\(=6650\ \text{cm}^2\) | ||
\(\text{Area in (m)}^2\) |
\(=\dfrac{1}{2}\times 0.95\times 1.40\) |
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\(=0.665\ \text{m}^2\) |
Calculate the area of the following triangles.
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a. \(42\ \text{cm}^2\)
b. \(17.5\ \text{m}^2\)
c. \(24\ \text{mm}^2\)
a. | \(\text{Area}\) | \(=\dfrac{1}{2}\times bh\) |
\(=\dfrac{1}{2}\times 12\times 7\) | ||
\(=42\ \text{cm}^2\) |
b. | \(\text{Area}\) | \(=\dfrac{1}{2}\times bh\) |
\(=\dfrac{1}{2}\times 5\times 7\) | ||
\(=17.5\ \text{m}^2\) |
c. | \(\text{Area}\) | \(=\dfrac{1}{2}\times bh\) |
\(=\dfrac{1}{2}\times 6\times 8\) | ||
\(=24\ \text{mm}^2\) |
Label the base (\(b\)) and draw and label a line indicating the perpendicular height (\(h\)), on the following triangles.
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Identify the base (\(b\)) and the perpendicular height (\(h\)), by labelling the following triangles.
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Luke builds a rectangular wooden deck in his backyard, with dimension 12 metres by 5 metres.
Luke is going to create a 0.5 metre wide path around the full perimeter of his deck.
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a. \(18\ \text{m}^2\)
b. \($1656\)
a. | \(\text{Area of path}\) | \(=2\times (12\times 0.5)+2\times (5\times 0.5)+4\times (0.5^2)\) |
\(=12+5+1\) | ||
\(=18\ \text{m}^2\) |
b. | \(\text{Cost of pavers}\) | \(=18\times $92\) |
\(=$1656\) |
A cement slab is laid in Yvette's backyard that forms an 8 metre by 4 metre rectangle.
Yvette is going to lay a 0.25 metre wide path around the full perimeter of her slab.
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a. \(6.25\ \text{m}^2\)
b. \($281.25\)
a. | \(\text{Area of path}\) | \(=2\times (8\times 0.25)+2\times (4\times 0.25)+4\times (0.25^2)\) |
\(=4+2+0.25\) | ||
\(=6.25\ \text{m}^2\) |
b. | \(\text{Cost of artificial turf}\) | \(=6.25\times $45\) |
\(=$281.25\) |
A poster has an area of 5250 square centimetres.
Find the area of the poster in square millimetres? (2 marks)
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\(525\ 000\ \text{mm}^{2}\)
\(\text{1 cm}^{2}\ = 10\ \text{mm}\ \times 10\ \text{mm} = 100\ \text{mm}^{2} \)
\(\text{5250 cm}^{2} = 5250 \times 100 = 525\ 000\ \text{mm}^{2}\)
Ken puts two cardboard squares together, as shown in the diagram below.
The squares have areas of 4 cm² and 25 cm².
Ken draws a line from the bottom left to top right, and shades the region above the line.
What is the area of the shaded region?
\(C\)
\(\text{Small square }\rightarrow 2\ \text{cm sides}\)
\(\text{Large square }\rightarrow 5\ \text{cm sides}\)
\(\text{Shaded Area}\) | \(=\dfrac{1}{2}\times bh\) |
\(=\dfrac{1}{2}\times 5\times 7\) | |
\(=17.5\ \text{cm}^2\) |
\(\Rightarrow C\)
Anthony is tiling one wall of a bathroom.
The wall has 2 identical windows as shown in the diagram below.
What is the total area Anthony has to tile? (2 marks)
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\(12.9\ \text{m}^2\)
\(\text{Area}\) | \(=(5.3\times 3)-2\times (1\times 1.5)\) |
\(=15.9-3\) | |
\(=12.9\ \text{m}^2\) |
A walled city has a land area of 950 hectares.
Express the area of the city in square kilometres. (2 marks)
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\(9.5\ \text{km}^2\)
\(\text{1 hectare}\ = 10\ 000\ \text{m}^{2}\)
\(\text{950 hectares}\ = 950 \times 10\ 000 = 9\ 500\ 000\ \text{m}^{2} \)
\(\text{1 km}^{2}\ = 1000\ \text{m} \times 1000\ \text{m}\ = 1\ 000\ 000\ \text{m}^{2}\)
\(\text{950 hectares}\ = \dfrac{9\ 500\ 000}{1\ 000\ 000} = 9.5\ \text{km}^{2} \)
Jim has a hobby farm with an area of 7 hectares.
What is the size of Jim's farm in square metres. (1 mark)
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\(70\ 000\ \text{m}^2\)
\(\text{1 hectare}\ = 10\ 000\ \text{m}^{2} \)
\(\text{7 hectares}\ = 7 \times 10\ 000 = 70\ 000\ \text{m}^{2} \)
Express an area of 0.003 square metres in square millimetres. (2 marks)
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\(3000\ \text{mm}^2\)
\(\text{1 m}^{2}\ =1000\ \text{mm}\times 1000\ \text{mm} =1\ 000\ 000\ \text{mm}^2\)
\(\text{0.003 m}^{2}\ = 0.003 \times 1\ 000\ 000 = 3000\ \text{mm}^{2} \)
Convert an area of 9 300 000 square metres into square kilometres. (1 mark)
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\(9.3\ \text{km}^2\)
\(\text{1 km}^{2} =1000\ \text{m}\times 1000\ \text{m}\ =1\ 000\ 000\ \text{m}^2\)
\(\text{9 300 000 m}^{2} =\dfrac{9\ 300\ 000}{1\ 000\ 000}=9.3\ \text{km}^2\)
A dining table has an area of 35 700 square centimetres.
Express this area in square metres. (1 mark)
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\(3.57\ \text{m}^2\)
\(\text{1 m}^{2}\ = 100\ \text{cm}\times 100\ \text{cm}\ = 10\ 000\ \text{cm}^{2} \)
\(\text{35 700 cm}^{2} = \dfrac{35\ 700}{10\ 000} = 3.57\ \text{m}^2\)
Convert an area of 500 square millimetres to square centimetres. (1 mark)
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\(5\ \text{cm}^2\)
\(\text{1 cm}^{2}\ =10\ \text{mm}\times 10\ \text{mm}\ =100\ \text{mm}^2\)
\(500\ \text{mm}^2 =\dfrac{500}{100} =5\ \text{cm}^2\)
A remote island has a land area of 4.6 square kilometres.
Convert this area into square metres. (1 mark)
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\(4\ 600\ 000\ \text{m}^2\)
\( \text{1 km}^{2}\ =1000\ \text{m} \times 1000\ \text{m} = 1\ 000\ 000\ \text{m}^2 \)
\(\text{4.6 km}^{2}\ = 4.6\times 1\ 000\ 000=4\ 600\ 000\ \text{m}^2 \)
Convert an area of 15 square metres to square centimetres. (1 mark)
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\(150\ 000\ \text{cm}^2\)
\(\text{1 m}^{2} = 100\ \text{cm}\times 100\ \text{cm}=10\ 000\ \text{cm}^2\)
\(\text{15 m}^{2}\ = 15 \times 10\ 000 = 150\ 000\ \text{cm}^2\)
Convert an area of 3 square centimetres to square millimetres. (1 mark)
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\(300\ \text{mm}^2\)
\(\text{1 cm}^{2} = 10\ \text{mm}\times 10\ \text{mm}\ =100\ \text{mm}^2\)
\(\text{3 cm}^{2} = 3 \times 100 = 300\ \text{mm}^2\)
Julia bought a kitchen rug with an area of 0.85 square metres.
What is the area of the kitchen rug in square centimetres? (2 marks)
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\(8500\ \text{cm}^{2} \)
\(\text{1 m}^{2} = 100\ \text{cm} \times 100\ \text{cm}\ =10\ 000\ \text{cm}^{2} \)
\(\text{0.85 m}^{2} = 0.85 \times 10\ 000 = 8500\ \text{cm}^{2} \)
Ben bought a dog mat with an area of 0.5 square metres.
What is the area of the dog mat in square centimetres?
\(C\)
\(\text{1 m}^{2} =100\ \text{cm}\times 100\ \text{cm} = 10\ 000\ \text{cm}^{2} \)
\(\text{0.5 m}^{2} = 0.5\times 10\ 000 =5000\ \text{cm}^2\)
\(\Rightarrow C\)
Bobby used 3 litres of varnish to paint the loungeroom floor.
The floor was a square with sides 6 metres long.
How many litres of varnish would he need to paint a rectangular floor which is 6 metres long and 10 metres wide? (2 marks)
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\(5\ \text{litres}\)
\(\text{Area of square floor}\)
\(=6^2\)
\(=36\ \text{m}^2\)
\(\text{Area of rectangular floor}\)
\(=6\times 10\)
\(=60\ \text{m}^2\)
\(\text{Paint needed for rectangular wall}\)
\(=\dfrac{60}{36}\times 3\)
\(=5\ \text{litres}\)
Shinji used 8 litres of paint to paint a wall.
The wall was a square with sides 4 metres long.
How many litres of paint would he need to paint a rectangular wall which is 3 metres high and 10 metres wide? (2 marks)
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\(15\ \text{litres}\)
\(\text{Area of square wall}\)
\(=4^2\)
\(=16\ \text{m}^2\)
\(\text{Area of rectangular wall}\)
\(=3\times 10\)
\(=30\ \text{m}^2\)
\(\text{Paint needed for rectangular wall}\)
\(=\dfrac{30}{16}\times 8\)
\(=15\ \text{litres}\)
Shinji used 8 litres of paint to paint a wall.
The wall was a square with sides 4 metres long.
How many litres of paint would he need to paint a rectangular wall which is 3 metres high and 10 metres wide? (2 marks)
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\(15\ \text{litres}\)
\(\text{Area of square wall}\)
\(=4^2\)
\(=16\ \text{m}^2\)
\(\text{Area of rectangular wall}\)
\(=3\times 10\)
\(=30\ \text{m}^2\)
\(\text{Paint needed for rectangular wall}\)
\(=\dfrac{30}{16}\times 8\)
\(=15\ \text{litres}\)
Vlad has a giant chess board that has an area of 4 square metres.
What is the area of the chess board in square centimetres? (2 marks)
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\(40\ 000\ \text{square centimetres}\)
\(\text{Strategy 1 (convert square metres):}\)
\(\text{1 m}^{2} = 100\ \text{cm}\ \times 100\ \text{cm}\ = 10\ 000\ \text{cm}^{2}\)
\(\text{Side length}\ =\sqrt{4} =2\ \text{m}\)
\(\text{Area}\ =2^2 = 4\ \text{m}\ = 4 \times 10\ 000 = 40\ 000\ \text{cm}^{2}\)
\(\text{Strategy 2 (convert sides to centimetres):}\)
\(\text{Side length}\ =\sqrt{4} =2\ \text{m}\ = 200\ \text{cm}\)
\(\text{Area}\ =200^2 = 40\ 000\ \text{square centimetres}\)
Jeremy's back deck is square in shape and has an area of 16 square metres.
What is the area of the deck in square centimetres? (2 marks)
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\(160\ 000\ \text{square centimetres}\)
\(\text{Strategy 1 (convert square metres):}\)
\(\text{1 m}^{2} = 100\ \text{cm}\ \times 100\ \text{cm}\ = 10\ 000\ \text{cm}^2 \)
\(\text{Side length of deck}\ =\sqrt{16} =4\ \text{m}\)
\(\text{Area} =4^2 = 16\ \text{m}^{2} = 16 \times 10\ 000 = 160\ 000\ \text{cm}^{2}\)
\(\text{Strategy 2 (convert side lengths):}\)
\(\text{Side length of deck}\ =\sqrt{16} =4\ \text{m}= 4 \times 100 = 400\ \text{cm}\)
\(\text{Area} =400^2 =160\ 000\ \text{cm}^{2}\)
A square fridge magnet has an area of 900 square millimetres.
What is the area of the fridge magnet in square centimetres? (2 marks)
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\(9\ \text{cm}^2\)
\(\text{Strategy 1 (convert square millimetres):}\)
\(\text{1 cm}^{2}\ = 10\ \text{mm}\ \times 10\ \text{mm}\ = 100\ \text{mm}^{2} \)
\(\text{Side length}\ =\sqrt{900}\ = 30\ \text{mm}\)
\(\text{Area} =30^2 =900\ \text{mm}^2 = \dfrac{900}{100} = 9\ \text{cm}^2 \)
\(\text{Strategy 2 (convert side lengths):}\)
\(\text{Side length}\ =\sqrt{900}\ =30\ \text{mm}= \dfrac{30}{10} = 3\ \text{cm}\)
\(\text{Area} =3^2 =9\ \text{cm}^2\)
A square table top has an area of 4225 square centimetres.
What is the area of the table top in square metres?
\(A\)
\(\text{Side length}\ =\sqrt{4225} =65\ \text{cm}= \dfrac{65}{10\ 000} = 0.65\ \text{m}\)
\(\text{Area}\ =0.65^2 =0.4225\ \text{square metres}\)
\(\Rightarrow A\)
A large square feature tile has an area of 15 625 square centimetres.
What is the area of the feature tile in square millimetres?
\(D\)
\(\text{Side length}\ =\sqrt{15\ 625}\ =125\ \text{cm} = 125 \times 10 = 1250\ \text{mm}\)
\(\text{Area}\ =1250^2 =1\ 562\ 500\ \text{square millimetres}\)
\(\Rightarrow D\)
A square table top has an area of 9025 square centimetres.
What is the area of the table top in square millimetres?
\(D\)
\(\text{Side length} =\sqrt{9025} =95\ \text{cm}= 95 \times 10 = 950\ \text{mm}\)
\(\text{Area}\ =950^2 =902\ 500\ \text{square millimetres}\)
\(\Rightarrow D\)
A holiday unit is shaped like a hexagon.
The dimensions of its floor plan are shown below.
What is the total area of the holiday unit in square metres? (2 marks)
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\(153\ \text{m}^2\)
\(\text{Holiday unit area}\) | \(=\text{Area of rectangle}+2\times \text{Area of triangle}\) |
\(=(9\times 14)+2\times\bigg(\dfrac{1}{2}\times 9\times 3\bigg)\) | |
\(=126+27\) | |
\(=153\ \text{m}^2\) |
A swimming pool is shaped like a hexagon.
The dimensions are given from the top view of the swimming pool.
What is the total area of the swimming pool in square metres? (2 marks)
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\(27\ \text{m}^2\)
\(\text{Pool area}\) | \(=\text{Area of rectangle}+2\times \text{Area of triangle}\) |
\(=(3\times 4)+2\times\bigg(\dfrac{1}{2}\times 3\times 5\bigg)\) | |
\(=12+15\) | |
\(=27\ \text{m}^2\) |
Binky used the paver pictured below to pave her pool area.
Altogether, she used 50 tiles.
What is the total area of Binky's pool area in square metres? (2 marks)
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\(13.5\ \text{m}^2\)
\(\text{Convert cm to metres:}\)
\(\rightarrow\ \ 60\ \text{cm}=0.6\ \text{m}\)
\(\rightarrow\ \ 30\ \text{cm}=0.3\ \text{m}\)
\(\text{Area of 1 paver}\) | \(=0.6^2-0.3^2\) |
\(=0.36-0.09\) | |
\(=0.27\ \text{m}^2\) |
\(\text{Total pool area paved}\) | \(=0.27\times 50\) |
\(=13.5\ \text{m}^2\) |
A plan of Bob's outdoor area is shown below.
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a. \(180\ \text{m}^2\)
b. \($7650\)
a. \(\text{Outdoor area}\)
\(\text{Total area}\) | \(=5\times 8+7\times 20\) |
\(=40+140\) | |
\(=180\ \text{m}^2\) |
b. | \(\text{Cost of tiling}\) | \(=180\times $42.50\) |
\(=$7650\) |
Bernie drew this plan of his timber deck.
Which expression gives the area of Bernie's timber deck?
\(B\)
\(\text{Total area}\) | \(=\text{Area}\ 1-\text{Area}\ 2\) |
\(=(c\times d)-(a\times b)\) |
\(\Rightarrow B\)
Vera drew this plan of her entertaining area.
Which expression gives the area of Vera's entertaining area?
\(D\)
\(\text{Total area}\) | \(=\text{Area}\ 1+\text{Area}\ 2+\text{Area}\ 3\) |
\(=(e\times f)+(a\times (d+b))+(c\times d)\) |
\(\Rightarrow D\)
Olive drew this plan of her lawn.
Which expression gives the area of Olive's lawn?
\(A\)
\(\text{Total area}\) | \(=\text{Area}\ 1+\text{Area}\ 2\) |
\(=(a\times b)+(c\times d)\) |
\(\Rightarrow A\)
A circular pool is located in a square lawn, as shown below.
The sides of the square lawn are 10 m in length.
The pool has a radius of 3 m.
The area of the lawn surrounding the pool, in square metres, is closest to
\(B\)
\(\text{Area of square}\) | \(=\text{side}^2\) |
\(=10^2\) | |
\(=100\ \text{m}^2\) |
\(\text{Area of pool}\) | \(=\pi r^2\) |
\(=\pi \times 3^2\) | |
\(= 28.27\dots\ \text{m}^2\) |
\(\therefore\ \text{Area of lawn}\) | \(=100-28.27\dots\) |
\(=71.72\dots\ \text{m}^2\) |
\(\Rightarrow B\)
A large mosaic tile artwork has been created inside a rectangle in the shape of a parallelogram as shown below.
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a. \(42\ \text{m}^2\)
b. \($3570\)
a. | \(\text{Area to be tiled}\) | \(=\text{Area of rectangle}-\text{Area of parallelogram}\) |
\(=11\times 6-8\times 3\) | ||
\(=42\ \text{m}^2\) |
b. | \(\text{Cost of tiling}\) | \(=\text{Shaded area}\times $85\) |
\(=42\times $85\) | ||
\(=$3570\) |
Rorke is designing a new logo that is made up of two identical parallelograms as shown below.
Calculate the area of the logo in square millimetres. (2 marks)
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\(306\ \text{mm}^2\)
\(\text{Area}\) | \(=2\times\text{base}\times \text{height}\) |
\(=2\times 17\times 9\) | |
\(=306\ \text{mm}^2\) |
\(\therefore\ \text{The area of the logo is }306\ \text{mm}^2.\)
A parallelogram has an area of 1872 square metres and a perpendicular height of 78 metres.
Calculate the base length of the parallelogram. (2 marks)
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\(24\ \text{m}\)
\(\text{Area}\) | \(=\text{base}\times \text{height}\) |
\(\therefore\ 1872\) | \(=b\times 78\) |
\(b\) | \(=\dfrac{1872}{78}\) |
\(=24\) |
\(\therefore\ \text{The base length of the parallelogram is }24\ \text{m.}\)
The parallelogram below has an area of 75.03 square centimetres and a base length of 12.3 centimetres.
Calculate the perpendicular height of the parallelogram. (2 marks)
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\(6.1\ \text{cm}\)
\(\text{Area}\) | \(=\text{base}\times \text{height}\) |
\(\therefore\ 75.03\) | \(=12.3\times h\) |
\(h\) | \(=\dfrac{75.03}{12.3}\) |
\(=6.1\) |
\(\therefore\ \text{The perpendicular height of the parallelogram is }6.1\ \text{cm.}\)
Calculate the area of the parallelogram below, in metres squared. (2 marks)
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\(84\ \text{m}^2\)
\(\text{Area}\) | \(=\text{base}\times \text{height}\) |
\(=6\times 14\) | |
\(=84\ \text{m}^2\) |
Calculate the area of the parallelogram below, in millimetres squared. (2 marks)
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\(115.73\ \text{mm}^2\)
\(\text{Area}\) | \(=\text{base}\times \text{height}\) |
\(=7.1\times 16.3\) | |
\(=115.73\ \text{mm}^2\) |
Calculate the area of the parallelogram below, in centimetres squared. (2 marks)
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\(48.96\ \text{cm}^2\)
\(\text{Area}\) | \(=\text{base}\times \text{height}\) |
\(=10.2\times 4.8\) | |
\(=48.96\ \text{cm}^2\) |
A sporting field in the shape of a square has a side length of 110 metres.
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a. \(12\ 100\ \text{m}^2\)
b. \($786.50\)
a. | \(\text{Area}\) | \(=s^2\) |
\(=110^2\) | ||
\(=12\ 100\ \text{m}^2\) |
b. | \(\text{Cost}\) | \(=\dfrac{12\ 100}{100}\times 6.50\) |
\(=121\times 6.50\) | ||
\(=$786.50\) |
The square below has a diagonal of 12 metres.
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a. \(\sqrt{72}\ \text{m}\)
b. \(72\ \text{m}^2\)
a. \(\text{Using Pythagoras to find the side length of the square:}\)
\(a^2+b^2\) | \(=c^2\) |
\(a^2+a^2\) | \(=12^2\) |
\(2a^2\) | \(=144\) |
\(a^2\) | \(=\dfrac{144}{2}=72\) |
\(a\) | \(=\sqrt{72}\ \text{m}\) |
b.
\(\text{Area}\) | \(=s^2\) |
\(=(\sqrt{72})^2\) | |
\(=72\ \text{m}^2\) |
Calculate the area of a square with a perimeter of 192 centimetres. (2 marks)
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\(2304\ \text{cm}^2\)
\(\text{Perimeter}\) | \(=192\ \text{cm}\) |
\(\therefore\ \text{Side}\) | \(=\dfrac{192}{4}\) |
\(=48\ \text{cm}\) |
\(\text{Area}\) | \(=s^2\) |
\(=48^2\) | |
\(=2304\ \text{cm}^2\) |
The following shape has a perimeter of 12.4 centimetres. Calculate its' area. (2 marks)
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\(9.61\ \text{cm}^2\)
\(\text{Perimeter}\) | \(=12.4\ \text{cm}\) |
\(\therefore\ \text{Side}\) | \(=\dfrac{12.4}{4}\) |
\(=3.1\ \text{cm}\) |
\(\text{Area}\) | \(=s^2\) |
\(=3.1^2\) | |
\(=9.61\ \text{cm}^2\) |