Another Short Trick to find HCF of Big Numbers

Duration: 5 min

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Inside: a video lesson and guided study material.

Module outline

  1. English Comprehension: Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Reading Comprehension, Vocabulary, Idioms and Phrases, Narrative Sequencing, Critical Reasoning
  2. Reasoning and Aptitude: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Analogy, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Blood Relations, Directions (Direction Test), Ranking, Order and Sequence, Logical Sequence Of Words, Seating Arrangements, Puzzle Solving (Puzzles), Syllogisms, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Data Sufficiency, Selection Decision Table (Decision Making), Calendar, Clock, Cubes & Dices, Data Arrangement, Venn Diagram, Analytical Reasoning (Counting Figures Reasoning), Number System, HCF LCM, Percentage, Ratio and Proportion (Ratios), Average, Profit and Loss, Simple Interest and Compound Interest, Speed Time and Distance, Mensuration and Geometry, Arithmetic, Mixture and Alligation, Age Problems, Data Interpretation, 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, Logical Deduction and Induction, Simplification and Approximation, Assembling and Grouping of Shapes, Transformation of Shapes, Three-Dimensional Patterns and Visualization, Cubes and Dice, Algebra, Traverse Surveying, Clocks and Calendars, Order, Ranking and Sequence, Constraint Puzzles, Syllogisms and Venn Diagrams, Ratio and Proportion, Mensuration, Permutations and Combinations, Project Monitoring, Resources and Safety, Profit, Loss and Discount, Sequences and Series, Powers, Surds and Logarithms, Subject-Verb Agreement, Sentence Completion, Geometry, Probability, Trigonometry, Measurement and Quantity Take-Off, Statistics, Data Sufficiency, Blood Relations, Speed, Time and Distance, Time and Work, Data Interpretation, Sequence and Series (Series), Algebra, Permutation and Combination, Combinatorics
  3. General Awareness: Physics, Chemistry, Biology, Geography, History, Polity, Indian Economy
  4. Computer Fundamentals: Basics of COA, Number System, Number Representation, Semiconductor Memories and Programmable Logic, Timing, Hazards and Testing, Processor Organization and Instructions, Number Systems and Codes, Combinational Logic Design, Combinational Logic Circuits, Number Systems and Codes
  5. Operating System: Introduction to OS, Unix OS, Linux OS
  6. C Programming: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
  7. OOPS with C++ & Java: OOPS with C++, Java
  8. Database Management System: Basics of DBMS, SQL
  9. MS Office: MS Office Applications
  10. Internet & Web Technologies: Website, Browser & Services, Internet Fundamentals, Web Design & Development, Protocols & Services
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

  1. 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. 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.

  3. 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.

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