Another Short Trick to find HCF of Big Numbers
Duration: 5 min
This video lesson is available to enrolled students.
Inside: a video lesson and guided study material.
Module outline
- Paper 1 | Reasoning Test: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Syllogisms, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Seating Arrangements, Blood Relations, Puzzle Solving (Puzzles), Venn Diagram, Analogy, Ranking, Order and Sequence, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Selection Decision Table (Decision Making), Logical Sequence Of Words, Cubes & Dices, Analytical Reasoning (Counting Figures Reasoning), Calendar, Alphabet and Word Tests, Numerical Reasoning, Number System, Averages, Mixtures and Alligation, Percentages, Series Completion, Analogy and Classification, Patterns in Two-Dimensional Figures, Coding and Decoding, Mathematical Operations, Direction Sense, Algebra, Logical Deduction and Induction, Syllogisms and Venn Diagrams, Critical Reasoning, Order, Ranking and Sequence, Reading Comprehension, Profit, Loss and Discount, Constraint Puzzles, Speed, Time and Distance, Traverse Surveying, Ratio and Proportion, Time and Work, Mensuration, Permutations and Combinations, Clocks and Calendars, Data Interpretation, Assembling and Grouping of Shapes, Transformation of Shapes, Three-Dimensional Patterns and Visualization, Cubes and Dice, Vocabulary, Blood Relations, Data Sufficiency
- Paper 1 | Numerical Analysis: Number System, HCF LCM, Percentage, Ratio and Proportion (Ratios), Average, Sequence and Series (Series), Powers and Exponents (Surds and Indices), Algebra, Statistics, Data Interpretation, Mental Ability, Arithmetic, Logarithm, Profit and Loss, Simple Interest and Compound Interest, Speed Time and Distance, Mixture and Alligation, Mensuration and Geometry, Permutation and Combination, Probability, Sequences and Series, Powers, Surds and Logarithms, Subject-Verb Agreement, Sentence Completion, Geometry, Sentence Structure and Correction, Data Sufficiency, Trigonometry, Measurement and Quantity Take-Off, Signal Space and Optimum Detection, Probability, Statistics, Algebra, Time and Work, Speed, Time and Distance, Data Interpretation, Graph Theory, Combinatorics
- Paper 1 | General Knowledge: State Wise GK, History, Geography, GK- Current Affairs, Static General Knowledge, Polity, Indian Economy
- Paper 1 | DBMS: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Transaction Management, Concurrency Control, Relational Calculus, Database Security & Authorization, Database Recovery
- Paper 1 | Data Communication & Network: Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, DLL: Error Control, DLL: Framing, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Net Layer:Routing Protocol, Transport Layer Services, TL: Congestion & UDP, Application Layer, Network Security, Security in Mobile and Wireless Computing, Input Output Organisation, File Management, Hardware Basics, Terms & Abbreviations, Protocols & Services, Network Access Technologies, Cyber Safety and Security, Basics of COA
- Paper 2 | System Analysis & Design: Fundamentals of Systems and Information Systems, SDLC and Development Approaches, Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Documentation and Software Requirements Specification (SRS), SDD and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management, Security, Risk Management & Maintenance, extras
- Paper 2 | Programming Language (Java): Java Fundamentals, OOPS with Java, Array, String, IO & References, Generic & Collections, Multithreading, Java, Miscellaneous, Control Flow, OOPS with C++, Stack, C Fundamentals, Arrays & Pointers, Object Oriented Technology, Control Flow & Looping, Introduction to Python
AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
This educational video, presented by Yash Jain from Knowledge Gate Eduventures, is a tutorial on finding the Highest Common Factor (HCF), also known as the Greatest Common Divisor (GCD). The video begins with an introduction to the topic, defining HCF and LCM, and then transitions to a practical problem: finding the GCD of three large numbers—1365, 1560, and 1755. The instructor demonstrates the prime factorization method as the primary technique. He systematically breaks down each number into its prime factors, writing the factor trees on the screen. For 1365, he shows the factorization as 3 × 5 × 7 × 13. For 1560, he factors it as 2³ × 3 × 5 × 13. For 1755, he factors it as 3³ × 5 × 13. The video concludes by identifying the common prime factors among all three numbers—3, 5, and 13—and multiplying them to find the GCD, which is 195. The final answer is confirmed as option (b) 195.
Chapters
0:00 – 2:00 00:00-02:00
The video opens with a title card for 'LCM & HCF' and then transitions to a classroom setting. An animated teacher stands by a green chalkboard that displays the text 'Highest Common Common Factor Factor (HCF)'. The instructor, Yash Jain, is visible in a small window. The video then moves to a new slide titled 'HCF of Big Numbers', which presents a multiple-choice question: 'Find the GCD of 1365, 1560, 1755?' with options (a) 95, (b) 195, (c) 295, (d) None of these. The instructor begins to explain the problem, setting up the context for the lesson.
2:00 – 5:00 02:00-05:00
The instructor begins the solution by demonstrating the prime factorization of the first number, 1365. He writes a factor tree, dividing 1365 by 3 to get 455, then 455 by 5 to get 91, and finally 91 by 7 to get 13. He concludes that 1365 = 3 × 5 × 7 × 13. He then proceeds to factor 1560, writing 1560 = 2³ × 3 × 5 × 13. Next, he factors 1755, showing 1755 = 3³ × 5 × 13. After establishing the prime factorization of all three numbers, he identifies the common prime factors: 3, 5, and 13. He multiplies these common factors (3 × 5 × 13) to find the GCD, which is 195. He then circles the correct answer, (b) 195, on the screen.
5:00 – 5:05 05:00-05:05
The video concludes with a black screen displaying the text 'THANKS FOR WATCHING' in white and orange letters. This is a standard closing slide for the educational content.
The video provides a clear, step-by-step demonstration of how to find the GCD of three large numbers using prime factorization. It begins by introducing the concept of HCF and then applies it to a specific problem. The core of the lesson is the method of breaking down each number into its prime factors, which is visually represented through factor trees. The key learning point is that the GCD is the product of the common prime factors. The video effectively uses on-screen annotations to guide the viewer through the calculation, making the process easy to follow and understand.

