Area Formulas

Area Formulas

by Hanna Drakos

​Area Formulas

​Grab your maths book and calculator so you are ready for this lesson!

​Example 1

Multiple Choice

Find the area of this square

• 5 cm

• 20 cm²

• 25 cm²

• 55 cm

Multiple Choice

What is the area?

• 12 cm²

• 14

• 14 cm²

• 24 cm²

​Example 2

Multiple Choice

Let's try one! Find the area of this circle:

• 25

• 78.5

• 31.4

​Example 3

Multiple Choice

Which of the following shows the correct working out when finding the AREA of the SECTOR shown in the diagram?

• $$\frac{75}{360}\times\left(\pi\times8\right)$$

• $$\frac{75}{360}\times\left(\pi\times8^2\right)$$

• $$\frac{75}{360}\times2\times\pi\times8$$

• $$\frac{75}{360}\times\left(2\times\pi\times8^2\right)$$

Multiple Choice

Calculate the area

• $$3cm$$

• $$3.44cm^2$$

• $$2.6cm^2$$

• $$4cm^2$$

​Complete the working in your book and then answer this in the next 3 slides.

​Application Question:

Multiple Choice

Mark uses 65 bricks to build $$1m^2$$  of wall. How many square metres can he build if he has 715 bricks?

Select the correct answer option for part a)

• 11

• 15

• 6

• 12

Multiple Choice

Remember that mark needs 65 bricks for $$1m^2$$  of wall.

Select your answer to part b).

• $$14.1m^2$$  

• $$15m^2$$  

• $$16.2m^2$$  

• $$18.9m^2$$  

Multiple Choice

Select your answer to part c). 

• 917 whole bricks

• 782 whole bricks

• 934 whole bricks

• 1010 whole bricks

​Application Question:

​Complete the working in your book and then answer this in the next 3 slides.

​Be careful - the diameter NOT the radius is given!

Multiple Choice

a) Area of the 30cm diameter pizza is:

• $$706.86cm^2$$  

• $$715cm^2$$  

• $$752cm^2$$  

• $$784cm^2$$  

Multiple Choice

b) the 30cm diameter pizza is now cut into 8 equal pieces. What is the area of each piece?  

• $$62.1cm^2$$  

• $$74.67cm^2$$  

• $$88.36cm^2$$  

• $$90.92cm^2$$  

Multiple Choice

c) Corey eats 3 slices and Anya eats 5 slices. How many more square centimetres of pizza does Anya eat?

• $$110cm^2$$  

• $$124.9cm^2$$  

• $$135.7cm^2$$  

• $$245.8cm^2$$