Short Trick to find LCM & HCF of fractions

Duration: 9 min

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Module outline

  1. Numerical Ability & Problem Solving: Speed Mathematics and Basic Mathematics, Arithmetic, Number System, HCF LCM, Divisibility Rules, Percentage, Ratio and Proportion (Ratios), Average, Profit and Loss, Simple Interest and Compound Interest, Mixture and Alligation, Time and Work, Pipe and Cistern, Speed Time and Distance, Age Problems, Partnership, Data Interpretation, Mental Ability, Sequence and Series (Series), Powers and Exponents (Surds and Indices), Algebra, Statistics, Logarithm, 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, Combinatorics
  2. Logical Reasoning: 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, Directions (Direction Test), Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Analytical Reasoning (Counting Figures Reasoning), Puzzle Solving (Puzzles), Calendar, Clock, Cubes & Dices, Logical Sequence Of Words, Venn Diagram, Data Arrangement, Inequality, Analogy, Ranking, Order and Sequence, Selection Decision Table (Decision Making), 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, Syllogisms and Venn Diagrams, Critical Reasoning, Order, Ranking and Sequence, Reading Comprehension, Profit, Loss and Discount, Constraint Puzzles, Traverse Surveying, Ratio and Proportion, Mensuration, Permutations and Combinations, Clocks and Calendars, Assembling and Grouping of Shapes, Transformation of Shapes, Three-Dimensional Patterns and Visualization, Cubes and Dice, Vocabulary, Blood Relations
  3. General Knowledge & Current Affairs (India + Rajasthan): History, Geography, Polity, Indian Economy, Static General Knowledge, State Wise GK, GK- Current Affairs, Environment, Physics
  4. Computer Fundamentals & Operating Systems: Basics of COA, Floating Point Rep, Digital Systems & Boolean Basics, Number Representation, Number System, Introduction to OS, File Management, Windows OS, Unix OS, Linux OS, Register Transfer and Microoperations, Virtual Memory
  5. Computer Networks: Introduction to CN, Data Communication, DLL: Error Control, DLL: Access Control, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Application Layer, Hardware Basics, Network Security
  6. Cyber Security: Cyber Threats and Malware Attacks, Role of Internet and Web Services, Security in Mobile and Wireless Computing, Electronic Data Interchange and E-Commerce, Physical Security and Cryptography Basics, Intrusion Detection Systems (IDS), Cyber Safety and Security, Ethical Hacking
  7. Programming (C & OOP): C Fundamentals, Control Flow, Arrays & Pointers, Functions, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, OOPS with C++, Operators & Expressions, Sorting Algorithms, Java Fundamentals, Java
  8. MS Office & Data Processing: MS Office Applications, Basics of DBMS
  9. Internet & Web Technology: Society, Law & Ethics, Terms & Abbreviations, Keyboard Shortcuts, Emerging Tech Trends, Artificial Intelligence, Emerging Technologies, Internet Fundamentals, Website, Browser & Services, Web Design & Development, Protocols & Services, Web Publishing & Hosting, Server Side & Security
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This educational video, presented by Yash Jain from Knowledge Gate Eduventures, provides a comprehensive lesson on finding the Least Common Multiple (LCM) and Highest Common Factor (HCF) of fractions. The lecture begins with an introduction to the topic, followed by the presentation of the core formulas. The LCM of fractions is defined as the LCM of the numerators divided by the HCF of the denominators, while the HCF of fractions is the HCF of the numerators divided by the LCM of the denominators. The instructor then demonstrates these concepts through a series of worked examples. The first example calculates the LCM of the fractions 7 1/2, 6 1/4, and 35/8, which involves converting mixed numbers to improper fractions (15/2, 25/4, 35/8), finding the LCM of the numerators (15, 25, 35) as 525, and the HCF of the denominators (2, 4, 8) as 2, resulting in an LCM of 525/2. The second example calculates the HCF of 3/2, 9/8, and 15/16, which involves finding the HCF of the numerators (3, 9, 15) as 3 and the LCM of the denominators (2, 8, 16) as 16, resulting in an HCF of 3/16. The final example calculates the HCF of 28/15, 98/35, and 56/25, yielding a result of 14/525. The video concludes with a 'Thanks for Watching' screen.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with a title card displaying 'LCM & HCF' against a digital, data-stream background. It then transitions to a classroom-style animation with a female teacher character and a male instructor, Yash Jain, in a picture-in-picture window. The main topic is introduced as 'Least Common Multiple (LCM)' and 'Highest Common Factor (HCF)'. The instructor begins to explain the concept of LCM of fractions, writing the formula on a digital whiteboard: LCM of (a/b, c/d, e/f) = LCM(a, c, e) / HCF(b, d, f). The on-screen text '9. LCM of fractions' is visible at the top of the whiteboard.

  2. 2:00 – 5:00 02:00-05:00

    The instructor continues to explain the concept of LCM of fractions, writing the formula LCM(a/b, c/d, e/f) = LCM(a, c, e) / HCF(b, d, f) on the whiteboard. He then transitions to the concept of HCF of fractions, writing the formula HCF(a/b, c/d, e/f) = HCF(a, c, e) / LCM(b, d, f). The on-screen text '9. LCM of fractions' remains visible. The instructor uses red ink to highlight the key components of the formulas, emphasizing the relationship between the LCM and HCF of the numerators and denominators. The copyright notice for 'KNOWLEDGE GATE EDUVENTURES' is visible at the bottom of the screen.

  3. 5:00 – 8:51 05:00-08:51

    The video presents a worked example for LCM of fractions: LCM(7 1/2, 6 1/4, 35/8). The instructor converts the mixed numbers to improper fractions: 15/2, 25/4, and 35/8. He then applies the formula, calculating LCM(15, 25, 35) = 525 and HCF(2, 4, 8) = 2, resulting in an LCM of 525/2. The next example is HCF(3/2, 9/8, 15/16). He calculates HCF(3, 9, 15) = 3 and LCM(2, 8, 16) = 16, resulting in an HCF of 3/16. The final example is HCF(28/15, 98/35, 56/25). He calculates HCF(28, 98, 56) = 14 and LCM(15, 35, 25) = 525, resulting in an HCF of 14/525. The video ends with a 'Thanks for Watching' screen.

The video provides a clear, step-by-step tutorial on calculating the LCM and HCF of fractions. It begins by establishing the fundamental formulas, which are the cornerstone of the lesson. The instructor then applies these formulas to three distinct problems, each demonstrating a different aspect of the calculation process, such as handling mixed numbers and simplifying the final result. The consistent use of a digital whiteboard for writing and the clear, methodical approach make the complex topic accessible for students preparing for competitive exams.

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