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This logical representation of numbers is the basis of all mathematical and algebraic calculations. A number system is
              generally categorised depending on its base. The four commonly used number systems are:
              •  Decimal number system
              •  Binary number system
              •  Octal number system
              •  Hexadecimal number system

              1.1.1 Decimal Number System
              Deca means ten, and as the name goes, the decimal number system is a positional value-based system with base 10
              in which the rightmost digit has the lowest position and is called the Least Significant Digit or LSD. The leftmost digit
              has the highest position and is known as the Most Significant Digit or MSD. The integer parts are represented by a
              positive power of 10, while the decimal parts are represented by a negative power of 10.


                                                             Definition


                    Decimal number system has base 10. The numerals or digits of Decimal number system are 0, 1, 2, 3, 4, 5, 6, 7, 8, 9.




              Say any number 123456.0789 is represented as,

                            10 5    10 4   10 3   10 2    10 1   10 0           10 -1  10 -2  10 -3   10 -4
                             1       2      3      4       5      6       .      0      7      8       9

              Decimal Odometer
              We have all seen an instrument called an odometer in automobiles. It is used to measure the distance travelled by the
              vehicle. The decimal odometer contains a set of wheels which have digits 0 to 9 written on them.

                                 Thousand       Hundred         Ten           Unit       Fractional part

                                     0             0             0             0              0

              A new vehicle has an odometer reading 00000. When a car starts moving, the rightmost tab
              keeps changing from 0, 1, 2 till 9. After the rightmost wheel has completed one rotation, the
              fractional tab is reset to 0 and 1 is carried to the units tab. When the unit wheel completes
              one rotation, the tens tab changes to 1 and reading shows 00010. This odometer can have
              maximum value 99999.

              1.1.2 Binary Number System
              With the invention of digital devices like computer, another branch of mathematics called Boolean Algebra was developed
              which used binary numbers containing only two digits 0 and 1.  Binary number system is the base for all modern electronic
              and computing devices.


                                                             Definition

                    Binary number system has base 2 and digits 0 and 1. Like Decimal number system, it is also a positional value-based
                    system where each digit has its weight denoted as a power of 2.







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