1) Draw a rectangle on the board and split it into ten sections. Ask a child how we can label each section of the rectangle (i.e. 1/10). Write 1/10 in each section...

1/10 | 1/10 | 1/10 | 1/10 | 1/10 | 1/10 | 1/10 | 1/10 | 1/10 | 1/10 |

1/10 | 1/10 | 1/10 | 1/10 | 1/10 | 1/10 | 1/10 | 1/10 | 1/10 | 1/10 |

3) Ask the children what fraction of the rectangle has been coloured (i.e. 1/10 + 1/10 + 1/10 = 3/10).

4) Explain that 3/10 can be written in another way... i.e. 0.3 (no units and three tenths)

5) Explain the features of the notation:

- The dot in between the 0 and the 3 is called the
**DECIMAL POINT**and we use it to separate the units from the tenths. - We always write in the 0 before the decimal point because it reminds us that the whole number is less than one.
- We say this number as "
**nought point three**" or "**zero point three**".

1/10 | 1/10 | 1/10 | 1/10 | 1/10 | 1/10 | 1/10 | 1/10 | 1/10 | 1/10 |

7/10 of the strip has been coloured.

7/10 can also be written as 0.7, which we say as "nought point seven" or "zero point seven".

**The trailing zeros after the decimal part of a decimal number**

Let’s look at this number 0.650

Decimal point | Tenths/10th | Hundredth/100th | Thousandth/1000th |

. | 6 | 5 | 0 |

The construction of this decimal part of a decimal number means

6/10 + 5/100 + 0/1000

We can see that 0 out of 1000 is nothing. So we can ignore this 0. What it means is that 0.65 is the same as 0.650

Similarly 0.6500 is the same as 0.65 because it means

6/10 + 5/100 + 0/1000 + 0/10000

**Exercises**

Questions | Answers |

Is 0.34 = 0.340 ? | True |

Is 345 = 3450 ? | False |

Is 0345 = 345 ? | True |

Which one is greater? | |

.09 and 0.10 | 0.10 |

0.0999999 and 0.10000000 | 0.10000000 |

3.01 and 2.99 | 3.01 |

0345 and 346 | 346 |

Is 16 x 10 = 016 ? | False |

Is 160.0 = 160 ? | True |

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