Number System for CDS & Defence Exams

By : Naveen Singh

Updated : Dec 3, 2020, 16:57

Number System plays a huge role in defence exams like UPSC NDA, UPSC CDS, UPSC CAPF, Air Force Group X & Y, ICG, CISF, Central Reserve Police Force (CRPF), etc. Scoring good marks in this topic increases the chances of getting selected in the defence exam. Number system can get divided into various subtypes depending on the base of the system. Bases act as a guiding force for smooth comprehension of the number system. It is also known as radix.

While making notes and strategizing your preparation, you should include number system practice questions and number system practice problems pdf. In this article, we have shared some framework points and tips to tackle the number system problem easily and quickly.

Important Number System Topics For Defence Exams



Number System

It is one of the methods of representing numbers. In other words, it is a mathematical notation of signifying numbers from the given set by using digits or symbols.


Bracket-Order-Division-Multiplication- Addition-Subtraction is the sequence that has to be followed from Left to Right while solving the given equations.


It is the least common multiple and highest common factors of the two natural numbers.

Tips to Solve Number System Questions For Defence Exams

  1. Study Number System formulas with examples thoroughly. It will elevate your paper-solving power.
  2. Check out the Number System syllabus for defence exams to avoid missing out on any relevant topic. Don’t forget to take the Number System online test for defence exams.
  3. In your leisure time, take the Number System quiz for the defence exam. It will bolster your preparation method.
  4. Study all the previous years' papers as it will help you to comprehend paper patterns and craft your preparation strategy accordingly.

Importance of Number System in Defence Exams

  • It checks your basic understanding of mathematics and quantitative ability to solve problems.
  • Computers outrightly depend on machine language. Any symbol, letter, or sign you type on the computer system gets transformed into machine language. This machine language consists of a number only. A better understanding of the number system is essential to comprehend the language of the computer.

Recommended Books To Practice Number System Questions

It is rightly said that reading can be a conversation. All books can talk but a good book is one that can teach a valuable life lesson. Here is the list of most recommended books for number system by experts:



Number Systems and the Foundation of Analysis

Elliot Mendelson

The Number Systems

Solomon Feferman

The Number System

H.A. Thurston

Introduction to Number Theory

Dr. Bilal Ahmad Chat, and Dr. Ather Aziz Raina

An Introduction To The Theory Of Numbers

Ivan Niven, and Herbert S Zuckerman

Why prepare Number System from BYJU'S Exam Prep?

Defence exams require the most extreme commitment, vigour, and direction. Experts at BYJU'S Exam Prep guarantee that each understudy comprehends the idea palpably. BYJU'S Exam Prep is one of the best education destinations for students preparing for banks, SSC, Railway, Defence, Teaching, UPSC, CLAT, CAT, GATE, JEE, Medical, and other competitive exams. It additionally leads to plenty of mock tests and Number System practice tests with answers that help the understudies in realising their dreams of a successful career. All the Number System study material pdf and Number System practice set are curated by experienced specialists. With BYJU'S Exam Prep, clearing defence exams or any tests is simple as it offers customised learning for each understudy as per their calibre.

FAQs (Frequently Asked Questions)

1. From where I can get Number System notes for defence exams?

You should try BYJU'S Exam Prep as they offer high-quality notes, Number System questions, and answers pdf and Number System tricks and tips for defence exams.

2. How many types of number systems are there?

There are four types of number systems:

  • Decimal number system
  • Binary number system
  • Octal number system
  • Hexadecimal number system

3.Why is the number system important?

The number system is an essential component of defence exams and most scoring topics. It enhances your ability to apprehend digital gadgets in the form of binary, octal & hexadecimal numbers .

4. Which is the biggest number system?

The biggest number system can be googolplex, ten to the googol power, or ( 10)^ ( 10^100).

5. How many questions get asked in the CDS exam from Number System?

The Exam pattern for CDS is as follows –


Number of Questions





Number System definition