An **infinite set **is a series of numbers that never ends.

The **natural numbers **are just the numbers starting from 1.

They are **1, 2, 3, 4, 5, ... etc.**

We say this set of numbers is **infinite** because the list will go on forever and will never end. We can always add one to the 'end' number.

The **whole numbers** are the counting numbers **and zero.**

They are **0, 1, 2, 3, 4, ... etc.**

This set of numbers is also **infinite.**

The** integers **are natural numbers, the negative numbers and zero.

They are** ... -4, -3, -2, -1, 0, 1, 2, 3, 4, ... etc.**

This set goes on forever at both 'ends' – at the start and the finish.

This set is infinite.

**Multiples of 3:**

3, 6, 9, 12, 15, ... etc.

This also goes on forever because we can always add 3 to the last number.

This set is **infinite.**

A **finite set **is a set of numbers that **doesn't **go on forever.

**The factors of 12:**

They are 1, 2, 3, 4, 6 and 12.

There are no more.

This set is **finite** as it does not go on forever. It has an end.

**Look at the multiples of 12 less than 50.**

They are 12, 24, 36, and 48.

There are no more, because we cannot go past 50.

This set is** finite **as it does not go on forever.

What a lot of different types of number to remember!

If you need a reminder while doing the questions, just click on the red button on the screen and it will show you this introduction again.

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