Reasoning

Number Systems and Series

164 Questions

Number systems and series questions assess the ability to manipulate numerical values and spot patterns. The focus includes digit arrangements, binary conversions, and identifying largest or smallest numbers. These reasoning tasks are common across major competitive examinations.

Digit manipulationLargest and smallest numbersBinary number systemsPositional numeral systemsNumber series ranking

Number Systems and Series Questions

Multiple choice maths operations adding and subtracting numbers using place value addition & subtraction mental additions and subtractions

Difference of the greatest 7 digit number and the smallest 5 digit number is 

  1. 998999

  2. 9989999

  3. 99899

  4. 998099
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

the greatest $7$ digit number is $9999999$


the smallest $5$ digit number is $10000$

we have to find the difference between these two numbers 

$9999999-10000=9989999$

So option $B$ is the answer

Multiple choice maths operations adding and subtracting numbers using place value addition & subtraction mental additions and subtractions

If three is subtracted from each of the following numbers, then which of the following options is the difference between the second highest number and the second digit of the highest number?
$489$     $541$     $654$      $935$       $873$.

  1. $0$
  2. $3$
  3. $1$
  4. $4$
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Given Numbers  489  541  654  935  873
 Subtraction  -3  -3  -3  -3  -3
 Required Numbers  486  538  651  932  870

Highest Number $\rightarrow$ $932$

Second digit of $932$  $\rightarrow$ $3$
Second highest Number $\rightarrow$ $870$
Second digit of $870$ $\rightarrow$  $7$ 
Difference between 7 and 3 $\rightarrow$ $4$
Hence, the required answer is $4$.

Multiple choice

What is the significance of the number '9' in the Indian Number System?

  1. It is the largest single-digit number.

  2. It is considered a lucky number.

  3. It is used as a placeholder for zero.

  4. It is the base of the Indian Number System.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In Indian culture, the number '9' is often associated with good luck and prosperity. It is commonly used in religious ceremonies, festivals, and other auspicious occasions.

Multiple choice

What is the term used to refer to the number system that uses a base other than 10?

  1. Non-Decimal Number System

  2. Binary Number System

  3. Hexadecimal Number System

  4. Octal Number System
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A non-decimal number system is a system that uses a base other than 10. Examples of non-decimal number systems include the binary system (base 2), the hexadecimal system (base 16), and the octal system (base 8).

Multiple choice

What is the term used to refer to the number system that uses a base of 2?

  1. Binary Number System

  2. Decimal Number System

  3. Hexadecimal Number System

  4. Octal Number System
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The binary number system is a base-2 number system that uses only two digits, 0 and 1. It is widely used in digital electronics and computer science.

Multiple choice

What is the term used to refer to the number system that uses a base of 16?

  1. Binary Number System

  2. Decimal Number System

  3. Hexadecimal Number System

  4. Octal Number System
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The hexadecimal number system is a base-16 number system that uses 16 digits (0-9 and A-F). It is widely used in computer science and digital electronics.

Multiple choice

What are some of the other number systems that have been used throughout history?

  1. The binary system

  2. The hexadecimal system

  3. The octal system

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The binary, hexadecimal, and octal systems are some of the other number systems that have been used throughout history.

Multiple choice

What is the name of the Indian number system that uses a base of 10?

  1. Decimal

  2. Binary

  3. Octal

  4. Hexadecimal
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The Indian number system that uses a base of 10 is called the decimal system. It is the most widely used number system in the world today.

Multiple choice

Which of the following is a base-10 number system?

  1. Hindu-Arabic

  2. Roman

  3. Chinese

  4. Mayan
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The Hindu-Arabic number system is a base-10 number system that originated in India and is now used worldwide.

Multiple choice

Which of the following numbers is the largest?

  1. 3456

  2. 4567

  3. 5678

  4. 6789
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

To determine the largest number, compare the digits from left to right. Since 6 is greater than 3, 4, and 5, the largest number is 6789.

Multiple choice

What is the difference between the greatest and smallest 3-digit numbers that can be formed using the digits 2, 5, and 8?

  1. 432

  2. 456

  3. 564

  4. 654
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

To find the greatest 3-digit number, arrange the digits in descending order (852), and for the smallest, arrange them in ascending order (258). The difference between 852 and 258 is 432.

Multiple choice

In the number 305, what is the role of the zero?

  1. It indicates the absence of a digit.

  2. It separates the hundreds and tens place.

  3. It increases the value of the digit to the left.

  4. It decreases the value of the digit to the left.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In the number 305, the zero serves as a placeholder to separate the hundreds place (3) from the tens place (0). It indicates that there are no tens in the number.

Multiple choice

What is the format of a Social Security Number?

  1. XXX-XX-XXXX.

  2. XXX XX XXXX.

  3. XXX-XX-XXXX.

  4. XXX XX XXXX
Reveal answer Fill a bubble to check yourself
A,C Correct answer
Explanation

The SSN is a nine-digit number in the format XXX-XX-XXXX.