Short Trick to find LCM & HCF of fractions

Duration: 9 min

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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, 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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