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Experiential Learning
#Number System
Find out more about the numeral system in different states of India. Write it in your notebook and type it in
a Word document as well.
#Activity
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 to the left of the decimal point is considered 0. The position of the second
digit to the left of the decimal point is considered 1, and so on. The position of the first digit to the right
of the decimal point is considered -1. The position of the second digit to the right of the decimal point
is considered –2, and so on.
In a decimal number system, each digit's value is determined by multiplying the digit itself by the weight
of its position within the number, and then summing up 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, in the number 724, the most significant digit is 7, and the least significant digit is 4.
The given table shows positional weight of decimal number (724) .
10
Hundereds Tens Units
Weights 10 2 10 1 10 0
Real Value of each digit 7 × 10 2 2 × 10 1 4 × 10 0
Result 700 20 4
Binary Number System
A computer is a machine made up of transistors, switches and other electronic components. All these electronic
components are in two mutually exclusive states, either ON or OFF. The two binary digits represent these two
states. Every instruction given to a computer is converted into 0’s and 1’s so that it can be understood and
implemented by the computer. Binary language is therefore known as the machine language.
The word 'binary' comes from 'Bi' meaning two. We see 'bi' in words such as ‘bicycle‘ (two wheels) or
‘binocular’ (two eyes).
Name Size (bits) Examples
A binary number is made up of only 0s and 1s.
Bit 1 Single digit either 0 or 1
Example of Binary Number: 110100 Nibble 4 Group of 4 digits
There is no 2, 3, 4, 5, 6, 7, 8 or 9 in Binary! Byte 8 Group of 8 digits
Word 16 Group of 16 digits
12 Plus (Ver. 4.0)-VII

