The Dual and Decimal Numeral Systems

# The Dual and Decimal Systems

 School year 9-11's (12-15 years) Subjects Concerned Mathematics, Informatics Concepts Involved Discovering Numeral Systems (binary) Aims of the PER* MSN 32 Duration of the Activities Watching the videos: 3' Activity: 60' Discussion with the scientist: 10' Modes of working Scholars' group work

*The experiments of the Thool Project occasionally allow the aims of PER to be exceeded. The teaching staff should be aware of this during the evaluation.

There are many numeral systems, but the one which is normally used is called the decimal system. It is based on the number 10 and uses the 10 digits 0 to 9. When we want to give the price of a product, or calculate something, or simply write an address on a postcard to a friend, we use the decimal system, which is known in the whole world.

Imagine that you are in another country, perhaps 2000 km. away, where the people speak another language. It is very warm there (or cold if you like, you can choose)). There is a table showing the outside temperature there, with values +45 or -25, which is a shock! The temperature is an analog signal in Informatics. How does an electronic device translate physical phenomena into digital signals? In digital systems the information is described using only the two digits 0 and 1, which represent a numeral system with base 2. This system is called a binary system and is used in all electronic devices to convert analog signals to digital signals.

If you want to work through examples of converting between decimal and binary numbers, Thymio can help you.