## Introduction

Surface measurements are part of our daily lives and answer our most common daily questions:

What is the area of this room?

What is the area of this apartment?

How many square meters of tiles do you need to cover this pool?

What is the area of this indoor soccer court?

What is the painted area of this wall?

## Surface and area

**Surface** is a two-dimensional quantity, while **area** is the measure of this magnitude, therefore, a number.

## Square meter

The fundamental unit of surface is called **square meter**. The square meter (m^{2}) is the measurement corresponding to the surface of a square with 1 meter side.

Multiples | Core Unit | Submultiples | ||||

square kilometer | square hectometer | square diameter | square meter | square decimeter | square centimeter | square millimeter |

km^{2} | hm^{2} | dam^{2} | m^{2} | dm^{2} | cm^{2} | mm^{2} |

1,000,000m^{2} | 10,000m^{2} | 100m^{2} | 1m^{2} | 0.01m^{2} | 0.0001m^{2} | 0.000001m^{2} |

Multiples | square kilometer | km^{2} | 1,000,000m^{2} |

square hectometer | hm^{2} | 10,000m^{2} | |

square diameter | dam^{2} | 100m^{2} | |

Core Unit | square meter | m^{2} | 1m^{2} |

Submultiples | square decimeter | dm^{2} | 0.01m^{2} |

square centimeter | cm^{2} | 0.0001m^{2} | |

square millimeter | mm^{2} | 0.000001m^{2} |

The dam^{2}, Oh M^{2} and km^{2} are used to measure large surfaces while dm^{2}, the cm^{2} and the mm^{2} They are used for small surfaces.

## Examples

**1)** Read the following measurement: 12.56m^{2}

km^{2} | hm^{2} | dam^{2} | m^{2} | dm^{2} | cm^{2} | mm^{2} |

12, | 56 |

It reads "12 square meters and 56 square centimeters". Each column of this table corresponds to one unit of area.

**2)** Read the following measurement: 178.3 m^{2}

km^{2} | hm^{2} | dam^{2} | m^{2} | dm^{2} | cm^{2} | mm^{2} |

1 | 78, | 30 |

It reads "178 square meters and 30 square decimeters".

**3)** Read the following measurement: 0.917 dam^{2}

km^{2} | hm^{2} | dam^{2} | m^{2} | dm^{2} | cm^{2} | mm^{2} |

0, | 91 | 70 |

It reads 9,170 square decimeters.

## Agrarian measures

Agrarian measures are used to measure field surfaces, crops, pastures, farms, etc. The main unit of these measures is the **are** (*The*). It has one multiple, the hectare (*there is*), and a submultiple, the centiare (*here*).

unity agrarian | hectare (ha) | area) | centiare (ca) |

Equivalence of value | 100a | 1st | 0.01a |

Remember if:

**1 ha = 1hm ^{2}1a = 1 dam^{2}1ca = 1m^{2}**