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. Section A | English: Vocabulary, Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Preposition, Sentence Correction (Error Correction), Sentence Completion (Fill in the blanks), Articles, Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Verbal Analogy (Word Based Analogy)
  2. Section A | Quant Aptitude: Ratio and Proportion (Ratios), Mixture and Alligation, Permutation and Combination, Number System, HCF LCM, Sequence and Series (Series), Speed Time and Distance, Arithmetic, Algebra, Powers and Exponents (Surds and Indices), Average, Age Problems, Percentage, Profit and Loss, Partnership, Time and Work, Simple Interest and Compound Interest, Mensuration and Geometry, Probability, Pipe and Cistern
  3. Section A | Reasoning: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Calendar, Clock, Blood Relations, Directions (Direction Test), Seating Arrangements, Ranking, Order and Sequence, Puzzle Solving (Puzzles)
  4. Section B | C Programming: C Programming by Yash Sir, Coding Questions by Yash Sir
  5. Section B | Data Structures: Algorithm Analysis, Greedy Algorithms, Time Complexity Analysis, Sorting Algorithms, Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs
  6. Section B | OOP (C++): Object Oriented Programming (OOPS), Programming in C++
  7. Section B | OS: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Windows OS
  8. Section B | Networking: 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, Hardware basics
  9. Section B | AI & Big Data Basics: AI & ML by Arun Sir, Big Data Systems
  10. Section C | Digital Electronics: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Analog-Digital Conversion
  11. Section A, C | Comp. Fundamentals, COA: Basics of COA, Floating Point Rep, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Register Transfer and Microoperations, Multiprocessors, Programming the Basic Computer
  12. MOCK TEST:
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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