# Functional Skills: Circles

## Functional Skills: Circles Revision

**Circles**

You will need to be able to identify and use properties of **circles** to then calculate the **area **and **circumference **of a circle.

Calculating the area and circumference involve working with a value called **pi **(\pi). \pi is the **ratio **of the circle’s circumference to its diameter (you don’t need to remember this) and is a decimal that never ends (\pi = 3.141592654...)

If you calculator has a \pi button then you can use this for calculations. However, you may be told to use \textcolor{orange}{3.14} or \textcolor{orange}{3.142} in place of \pi instead.

**Properties of Circles**

The **circumference **of a circle is the length around the outside, or in other words – the perimeter.

The **centre **of a circle is the point exactly in the middle, where the distance to the **circumference **is equal from any direction.

The **diameter **of a circle is the distance from one side of the circle to the other, passing through the **centre**.

The **radius **of a circle is the distance from the **centre **to the **circumference**. The **radius **is always half of the **diameter**.

## Follow Our Socials

Our Facebook page can put you in touch with other students of your course for revision and community support. Alternatively, you can find us on Instagram or TikTok where we're always sharing revision tips for all our courses.

**Area and CircumferenceÂ **

**Area **of a circle = \pi r^2

**Circumference** of a circle =\pi d = 2\pi r

r= **radius** and d= **diameterÂ **

**Example 1: Calculating Area**

Calculate the **area **of the circle shown on the right with a **diameter **of 4.8 cm to 1 decimal place.

Use \pi = 3.14

**[3 marks]**

The **diameter **of a circle is double the length of the **radius**, so

**radius **=\dfrac{4.8}{2}=2.4 cm

We know that the **area **of a circle =\pi r^2

Thus, using r=2.4 and \pi =3.14,

**area **of the circle = 3.14 \times 2.4^2=\textcolor{orange}{18.1} cm^2 (1 dp)

**Example 2: Calculating Circumference**

Calculate theÂ **circumference**** **of the circle shown on the right with a **radius **of 2.9 cm to 1 decimal place.

Use \pi = 3.14

**[2 marks]**

We know that the **circumference **of a circle = \pi d = 2\pi r

Thus, using r=2.9 and \pi =3.14,

**circumferenceÂ **of the circle =2 \times 3.14 \times 2.9=\textcolor{orange}{18.2} cm (1 dp)

## Functional Skills: Circles Example Questions

**Question 1:Â **The circle below has a radius of 8.6 cm.

**a)Â **Calculate the circumference of the circle to 2 decimal places.

**[2 marks]**

**b)** Calculate the area of the circle to 2 decimal places.

**[2 marks]**

Use \pi=3.14

**a) **Circumference = 2\times \pi \times r

Circumference of the circle = 2\times 3.14\times 8.6=54.01 cm to 2 decimal places.

**b) **Area = \pi r^2

Area of the circle = 3.14 \times 8.6^2=232.23 cm^2 to 2 decimal places.

**Question 2:Â **Calculate the area of the circle below, which has a diameter of 11.3 cm.

Give your answer to 2 decimal places and use \pi=3.14

**[2 marks]**

Area = \pi r^2

We know that the diameter is double the length of the radius, so r=\dfrac{11.3}{2}=5.65 cm

Thus the area of the circle = 3.14 \times 5.65^2=100.24 cm^2 to 2 decimal places.

**Question 3:Â **The circumference of a circle is 11.932 cm. Use \pi=3.14, to find the area of the circle, giving your answer to 2 decimal places.

**[3 marks]**

We know that circumference = 2 \pi r

So 11.932= 2\times3.14\times r

\rArr r = \dfrac{11.932}{2\times3.14}=1.9 cm

Area = 3.14 \times 1.9^2=11.34 cm^2 to 2 decimal places.

**Question 4:Â **Calculate the circumference of the circle below with diameter of 3.2 m, giving your answer correct to 2 decimal places.

Use \pi =3.14

**[2 marks]**

Using circumference = \pi d

The circumference of the circle = 3.14 \times 3.2=10.05 m to 2 decimal places.

## Functional Skills: Circles Worksheet and Example Questions

### Circles L2

FS Level 2NewOfficial PFS[responsive-flipbook id=”pfs_pocket_revision_guide_-_sample”]

## Revision Products

### Functional Skills Maths Level 2 Pocket Revision Guide

Revise and practice for your functional skills maths level 2 exam. All topics covered in this compact revision guide.

### Functional Skills Maths Level 2 Mini Tests

Practice for your functional skills Maths level 2, questions from every topic included.

### Functional Skills Maths Level 2 Revision Cards

Revise for functional skills maths level 2 easily and whenever and wherever you need. Covering all the topics, with revision, questions and answers for every topic.

### Functional Skills Maths Level 2 Practice Papers

This 5 set of Functional Skills Maths Level 2 practice papers are a great way to revise for your Functional Skills Maths Level 2 exam. These practice papers have been specially tailored to match the format, structure, and question types used by each of the main exam boards for functional skills Maths. Each of the 5 papers also comes with a comprehensive mark scheme, so you can see how well you did, and identify areas to improve on.

### Functional Skills Maths Level 2 Practice Papers & Revision Cards

This great value bundle enables you to get 5 functional skills maths level 2 practice papers along with the increasingly popular flashcard set that covers the level 2 content in quick fire format.