Educational Resource — Mathematical Secondary Education — UD.4- decimal numbers and Decimal Metric System

Decimal numbers are used to express quantities smaller than the unit and by using the tenths, hundredths, thousandths,... a degree of precision is reached to the extent that it only depends on the number of significant decimal numbers. Therefore, the decimal numbers and the decimal metric system are presented together.
In this unit, decimal numbers are part of the set of rational numbers: all of them can be expressed in the form of a fraction.