Number System Conversion
As we know, the number system is a form of expressing the numbers.
In number system conversion, we will study to convert a number of
one base, to a number of another base. There are a variety of number
systemssuch as binary numbers, decimal numbers, hexadecimal
numbers, octal numbers, which can be exercised.
In this article, you will learn the conversion of one base number to
another base number considering all the base numbers such as
decimal, binary, octal and hexadecimal with the help of examples.
Here, the following number system conversion methods are explained.
• Binary to Decimal Number System
• Decimal to Binary Number System
• Octal to Binary Number System
• Binary to Octal Number System
• Binary to Hexadecimal Number System
• Hexadecimal to Binary Number System
Get the pdf of number system with a brief description in it. The
general representation of number systems are;
Decimal Number – Base 10 – N10
Binary Number – Base 2 – N2
Octal Number – Base 8 – N8
Hexadecimal Number – Base 16 – N16
Number System Conversion Table
Binary Octal Decimal Hexadecimal
Numbers Numbers Numbers Numbers
0000 0 0 0
0001 1 1 1
0010 2 2 2
0011 3 3 3
0100 4 4 4
0101 5 5 5
0110 6 6 6
0111 7 7 7
1000 10 8 8
1001 11 9 9
1010 12 10 A
1011 13 11 B
1100 14 12 C
1101 15 13 D
1110 16 14 E
1111 17 15 F
Number System Conversion Methods
Number system conversions deal with the operations to change the
base of the numbers. For example, to change a decimal number with
base 10 to binary number with base 2. We can also perform the
arithmetic operations like addition, subtraction, multiplication on the
number system. Here, we will learn the methods to convert the
number of one base to the number of another base starting with the
decimal number system. The representation of number system base
conversion in general form for any base number is;
(Number)b = dn-1 dn-2—–.d1 d0 . d-1 d-2 —- d-m
In the above expression, dn-1 dn-2—–.d1 d0 represents the value of
integer part and d-1 d-2 —- d-m represents the fractional part.
Also, dn-1 is the Most significant bit (MSB) and d-m is the Least
significant bit (LSB).
Now let us learn, conversion from one base to another.
Related Topics
Binary Number Hexadecimal Number
System System
Octal Number Number System For
System Class 9
Decimal to Other Bases
Converting a decimal number to other base numbers is easy. We have
to divide the decimal number by the converted value of the new base.
Decimal to Binary Number:
Suppose if we have to convert decimal to binary, then divide the
decimal number by 2.
Example 1. Convert (25)10 to binary number.
Solution: Let us create a table based on this question.
Operation Output Remainder
25 ÷ 2 12 1(MSB)
12 ÷ 2` 6 0
6÷2 3 0
3÷2 1 1
1÷2 0 1(LSB)
Therefore, from the above table, we can write,
(25)10 = (11001)2
Decimal to Octal Number:
To convert decimal to octal number we have to divide the given
original number by 8 such that base 10 changes to base 8. Let us
understand with the help of an example.
Example 2: Convert 12810 to octal number.
Solution: Let us represent the conversion in tabular form.
Operation Output Remainder
128÷8 16 0(MSB)
16÷8 2 0
2÷8 0 2(LSB)
Therefore, the equivalent octal number = 2008
Decimal to Hexadecimal:
Again in decimal to hex conversion, we have to divide the given
decimal number by 16.
Example 3: Convert 12810 to hex.
Solution: As per the method, we can create a table;
Operation Output Remainder
128÷16 8 0(MSB)
8÷16 0 8(LSB)
Therefore, the equivalent hexadecimal number is 80 16
Here MSB stands for a Most significant bit and LSB stands for a least
significant bit.
Other Base System to Decimal Conversion
Binary to Decimal:
In this conversion, binary number to a decimal number, we use
multiplication method, in such a way that, if a number with base n has
to be converted into a number with base 10, then each digit of the
given number is multiplied from MSB to LSB with reducing the power
of the base. Let us understand this conversion with the help of an
example.
Example 1. Convert (1101)2 into a decimal number.
Solution: Given a binary number (1101)2.
Now, multiplying each digit from MSB to LSB with reducing the power
of the base number 2.
1 × 23 + 1 × 2 2 + 0 × 21 + 1 × 20
=8+4+0+1
= 13
Therefore, (1101)2 = (13)10
Octal to Decimal:
To convert octal to decimal, we multiply the digits of octal number
with decreasing power of the base number 8, starting from MSB to
LSB and then add them all together.
Example 2: Convert 228 to decimal number.
Solution: Given, 228
2 x 81 + 2 x 80
= 16 + 2
= 18
Therefore, 228 = 1810
Hexadecimal to Decimal:
Example 3: Convert 12116 to decimal number.
Solution: 1 x 162 + 2 x 161 + 1 x 160
= 16 x 16 + 2 x 16 + 1 x 1
= 289
Therefore, 12116 = 28910
Hexadecimal to Binary Shortcut Method
To convert hexadecimal numbers to binary and vice versa is easy, you
just have to memorize the table given below.
Hexadecimal Number Binary
0 0000
1 0001
2 0010
3 0011
4 0100
5 0101
6 0110
7 0111
8 1000
9 1001
A 1010
B 1011
C 1100
D 1101
E 1110
F 1111
You can easily solve the problems based on hexadecimal and binary
conversions with the help of this table. Let us take an example.
Example: Convert (89)16 into a binary number.
Solution: From the table, we can get the binary value of 8 and 9,
hexadecimal base numbers.
8 = 1000 and 9 = 1001
Therefore, (89)16 = (10001001)2
Octal to Binary Shortcut Method
To convert octal to binary number, we can simply use the table. Just
like having a table for hexadecimal and its equivalent binary, in the
same way, we have a table for octal and its equivalent binary number.
Octal Number Binary
0 000
1 001
2 010
3 011
4 100
5 101
6 110
7 111
Example: Convert (214)8 into a binary number.
Solution: From the table, we know,
2 → 010
1 → 001
4 → 100
Therefore,(214)8 = (010001100)2
Practice Problems on Number System Conversion
1. Convert 14610 into a binary number system
2. Convert 1A716 into the decimal number system
3. Convert (110010)2 into octal number system
4. Convert DA216 into the binary number system
5. Convert 46528 into the binary number system
Frequently Asked Question on the Number System Conversion
Why do we need the number system conversion?
One of the most important applications of the number system is in
computer technology. Generally, a computer uses the binary number
system, but humans will use the hexadecimal number system, as it is
easier to understand. For this reason, the number system conversion
is required.
What is meant by the base 2 number system?
The base 2 number system is called the binary number system. It uses
only two digits, such as 0, 1. For example, the number 6 is represented
by 0110 (or) 110.
Write down the conversion procedure from decimal to binary number
system?
The steps to convert the decimal number system to binary number
system are:
Divide the given number by 2
Now, use the obtained quotient for the next iteration
Obtain the remainder for the binary number
Repeat the steps until the quotient is equal to 0
What is meant by the base 8 number system?
The base 8 number system is called the octal number system. It uses
the digits such as 0, 1, 2, 3, 4, 5, 6, 7.
What is meant by the hexadecimal number system?
The hexadecimal number system is called the base 16 number
system. It uses the digits from 0 to 9, and A, B, C, D, E, F
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