Unit 8.1

# Cardinal numbers: Decimals, Tens and Hundreds

## Introduction

**Cardinal numbers **give information about how many people or things there are.

**Decimals** are the smallest of the numbers, being the **result of fractions**. **Ten numbers** go from 1 to 99. **Hundred numbers** go from 100 to 999.

## Form

**Decimal** numbers are the **result of a fraction.**

- They normally have a
**comma or**a**point**between the whole number and the decimals.

**Ten** numbers have **ten as its base. **Despite, the numbers from **1 to 9 **are commonly called** unities.**

- Plain form:
**number + 0** - They have
**specific names**from 0 to 20 - From 20 to 99 the numbers
**follow a pattern**to name them: Using a hyphen in between the ten number and the unit.

Unities from 1 to 9 |
Tens from 11 to 19 |
Tens from 10 to 90 |
Tens + unities |

one | eleven | ten | twenty-one |

two | twelve | twenty | twenty-two |

three | thirteen | thirty | twenty-three |

four | fourteen | fourty | twenty-four |

five | fifteen | fifty | twenty-five |

six | sixteen | sixty | twenty-six |

seven | seventeen | seventy | twenty-seven |

eight | eighteen | eighty | twenty-eight |

nine | nineteen | ninety | twenty-nine |

The **hundred** numbers have **one hundred as its base.**

- Plain form:
**number + 00** - Their name is: how the
**number**in the beginning is called**+ hundred** - 100 can be called ‘
**one**hundred’ or ‘**a**hundred’ - If there are more numbers after the hundred number, they need to be mentioned as normal (ten number). Sometimes, we use ‘and’ in between the hundred number and the ten number.
- From 100 to 999

Hundreds from 100 to 900 |
Hundreds + Unities |
Hundreds + Tens |

one hundred | one hundred and one | one hundred and ten |

two hundred | one hundred and two | one hundred and twenty |

three hundred | one hundred and three | one hundred and thirty |

four hundred | one hundred and four | one hundred and forty |

five hundred | one hundred and five | one hundred and fifty |

six hundred | one hundred and six | one hundred and sixty |

seven hundred | one hundred and seven | one hundred and seventy |

eight hundred | one hundred and eight | one hundred and eighty |

nine hundred | one hundred and nine | one hundred and ninety |

## Example

**DECIMALS**:

- 567/100 = 5,67
- Five point sixty-seven

**TEN NUMBERS**:

- 10 (ten)
- 25 (twenty-five)

**HUNDRED NUMBERS: **

- 100 (one hundred)
- 871 (eight hundred seventy-one)

## Use

We normally use the singular form of the numbers – when we are naming a concrete figure.

We use the plural form when we are not speaking about a concrete number, but in general terms. We don’t even use a whole number for that:

- Hundreds of + noun (“There were hundreds of adolescents in that party”)

In formal writing it is better to write the number in letters when it is a short figure.