Number System
“A set of values used to represent different quantities is known as Number System“.
OR
Number systems are the technique to represent numbers in the computer system architecture, every value that you are saving or getting into/from computer memory has a defined number system.
Computer architecture supports following number systems.
» Binary number system
» Octal number system
» Decimal number system
» Hexadecimal (hex) number system
Binary Number System : -
A Binary number system has only two digits that are 0 and 1. Every number (value) represents with 0 and 1 in this number system. The base of binary number system is 2, because it has only two digits.
On represent as 1 and Off represent as 0. 0 is not actually no signal but signal at a lower voltage. The binary number system is very efficient for computers, but not for humans. The binary numbers 0 and 1 called a bit. The computer always calculates input in binary form. Right most digit is called Least Significant bit (LSB). Left most digit is called Most Significant bit(MSB)
Octal number system : -
Octal number system has only eight (8) digits from 0 to 7. Every number (value) represents with 0,1,2,3,4,5,6 and 7 in this number system. The base of octal number system is 8, because it has only 8 digits.
Decimal number system :-
Decimal number system has only ten (10) digits from 0 to 9. Every number (value) represents with 0,1,2,3,4,5,6, 7,8 and 9 in this number system. The base of decimal number system is 10, because it has only 10 digits.
Hexadecimal number system : -
A Hexadecimal number system has sixteen (16) alphanumeric values from 0 to 9 and A to F. Every number (value) represents with 0,1,2,3,4,5,6, 7,8,9,A,B,C,D,E and F in this number system. The base of hexadecimal number system is 16, because it has 16 alphanumeric values. Here A is 10, B is 11, C is 12, D is 13, E is 14 and F is 15.
Question
Question 1 : Which of the following is not a type of number system?
1. Positional
2. Non-Positional
3. Octal
4. Fractional
Answer
Correct Anaswer : 4
Explanation:
There are two main types of number systems : Positional & Non-positional. Positional System uses digits for the representation whereas, non-positional number systems use certain symbols for the representation of numbers. Octal is a type of positional number systems with base 8.
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Question 2 : How is the number 5 represented in non-positional number system?
1. IIIII
2. 5
3. V
Answer
Correct Anaswer : 1
Explanation:
In a non-positional number system, 1 is represented as I, 2 as II, 3 as III, 4 as IIII and therefore, 5 is represented as IIIII. This number system uses symbols for the representation of digits.
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Question 3 : The base is the total number of digits in a number system.
1. TRUE
2. FALSE
Answer
Correct Anaswer : 1
Explanation:
The statement is true. In a positional number system, base is the number of digits the system comprises. For example, a binary number system comprises of only 2 digits, 0 and 1, therefore its base is 2. Similarly, the decimal system comprises 10 digits 0 to 9, therefore its base is 10.
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Question 4 : The LSB and MSB of 1243247 are ____ and ____
1. 1, 7
2. 4, 7
3. 7, 1
4. 4, 1
Answer
Correct Anaswer : 3
Explanation:
The LSB or the least significant bit is the rightmost digit at the zeros position. The MSB or the most significant bit is the leftmost digit.
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Question 5 : A device that uses positional notation to represent a decimal number.
1. Abacus
2. Calculator
3. Pascaline
4. Computer
Answer
Correct Anaswer : 1
Explanation:
Abacus was used to doing arithmetic calculations around 2500 years ago. Pascaline was the pascal’s calculator by Blaise Pascal invented for doing laborious calculations.
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