Page 10 - trackpad v5.1 class 7 flipbook
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DATA REPRESENTATION
The smallest piece of data that can be recognised and Founder of zero
used by the computer is known as the bit or binary
digit. A group of eight bits is called a byte. A bit is a single binary value i.e., 1 or 0. A computer is an
electronic device that has two states: On and Off. These two states of the computer are represented
by two digits: 1 and 0. Here, 1 represents the electronic state On, and 0 represents the electronic
state Off.
WHAT IS NUMBER SYSTEM?
A number system is a way to express quantities used for counting, comparing amounts,
performing calculations and representing values. A computer represents all kinds of data and
information like text, numbers, audio and video in binary form. The total number of digits used
in a number system is called its base or radix. There are four types of number systems: Binary
number system, Decimal number system, Octal number system and Hexadecimal number
system.
PURE The numerical digits, 1, 2, ..... ,9 are based on the Hindu-Arabic numeral system developed
FACT over 1000 years ago.
DECIMAL NUMBER SYSTEM
A number system made up of 10 digits from 0 to 9, is known as decimal number system. The
base of the decimal number system is 10. It is also known as the base-10 system.
In the decimal number system, the position of the first digit towards the left side of the decimal
point is 0. The position of the second digit towards the left side of the decimal point is 1. Similarly,
the position of the first digit towards the right side of the decimal point is –1. The position of the
second digit towards the right side of the 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
Weights 10 2 10 1 10 0 . 10 -1 10 -2
In simple words, the successive position to the left of the decimal point represents units, tens,
hundreds, thousands, and so on.
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 the 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 the Most Significant Digit (MSD).
8 Pro (V5.1)-VII

