Page 10 - Touchpad_Plus_V3.2_Class 7
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The  total  number of  digits used  in a number system is  called  its  base  or  radix.  Therefore,

                  when someone says that he is working with number system of radix 2, it means base 2, i.e.,
                  binary number system. The base is written after the number as subscript such as (512) . In
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                  this example, the number 10 is written as the subscript to express the number in 512 decimal
                  number system.

                  There are four types of number systems, which are as follows:

                  1.  Decimal number system
                  2.  Binary number system

                  3.  Octal number system

                  4.  Hexadecimal number system

                  The decimal number system is used in general. However, the computers use binary number
                  system. The octal and hexadecimal number systems are also used in the computer.

                  Decimal Number System

                  The decimal number system is a standard number system for denoting numbers. It consists
                  of ten digits from 0 to 9. Only these digits can be used to represent numeric value in decimal
                  number system. Hence, the base of decimal number system is 10. The decimal number system is

                  the most widely used number system. The value represented by individual digit depends on the
                  weight and position of the digit in the number.
                  The position of the first digit towards left side of the decimal point is 0. The position of second

                  digit towards left side of the decimal point is 1. Similarly, the position of the first digit towards
                  right side of decimal point is –1. The position of second digit towards right side of decimal point
                  is –2, and so on.

                  The place value of the digits according to position and weight is as follows:

                             Position          2           1          0                      –1         –2
                                                                                  •
                                                 2          1          0                      –1          –2
                             Weight           10          10         10                     10         10

                  The value of a number is determined by multiplying the digits with the weight of their position
                  and adding the results. This method is known as expansion method. The right-most digit

                  of the number has the lowest weight. This digit is called Least Significant Digit (LSD). The
                  left-most digit of a number has the highest weight. This digit is called Most Significant Digit
                  (MSD). For example, digit 7 in the number 724 is the most significant digit and 4 is the least
                  significant digit.

                  The following table shows positional weight of decimal number (724) .
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                8       Plus (Ver. 3.2)-VII
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