Short Trick to Find A B C given some mA = nB = pC

Duration: 5 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 provides a comprehensive tutorial on solving ratio problems involving three variables, specifically focusing on the scenario where variables are related by a common equation. The instructor, Yash Jain, explains how to find the ratio A:B:C when given an equation where the variables are multiplied by different constants, such as mA = nB = pC. The core technique involves setting the equation to a constant 'k' to isolate each variable, expressing them as fractions, and then finding the Least Common Multiple (LCM) of the denominators to simplify the result into whole numbers. This method is presented as a standard approach for competitive exams.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video begins with a title slide displaying "RATIO & PROPORTION" in bold black text next to a colorful 3D pie chart. The instructor, Yash Jain, appears in a small window and introduces the topic. A slide defines "Ratio" as "a comparison of 2 quantities," accompanied by a diagram illustrating parts and a whole. The lesson then transitions to a specific problem type titled "Finding A:B:C where mA = nB = pC". The first example problem is displayed on a yellow background: "If 3A = 5B = 6C, find A : B : C?". The instructor underlines the numbers 3, 5, and 6 to identify them as the coefficients m, n, and p.

  2. 2:00 – 5:00 02:00-05:00

    The instructor demonstrates the solution by setting the entire equation equal to a constant variable 'k', writing "3A = 5B = 6C = k". He isolates each variable to express them in terms of k: A = k/3, B = k/5, and C = k/6. He then constructs the ratio A:B:C as k/3 : k/5 : k/6. To simplify this into whole numbers, he calculates the Least Common Multiple (LCM) of the denominators 3, 5, and 6, which is 30. He multiplies each term of the ratio by 30, resulting in the final integer ratio 10 : 6 : 5. He also writes the general formula A:B:C = 1/m : 1/n : 1/p.

  3. 5:00 – 5:27 05:00-05:27

    The instructor briefly presents a second example problem: "If 2A = 3B = 4C, find A : B : C?". He applies the general formula A:B:C = 1/2 : 1/3 : 1/4. He calculates the LCM of 2, 3, and 4 as 12. Multiplying the terms by 12 yields the ratio 6 : 4 : 3. The video concludes with a black screen displaying the text "THANKS FOR WATCHING" in orange and white font.

The lesson progresses logically from basic definitions of ratio to complex algebraic applications. The key takeaway is the method of equating terms to a constant 'k' to isolate variables, followed by finding the LCM to convert fractional ratios into integers. The instructor demonstrates this with two distinct examples, reinforcing the concept that the ratio of variables is the inverse of their coefficients. This systematic approach ensures accuracy in solving ratio and proportion problems found in competitive exams, providing students with a reliable shortcut for similar questions.

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