Tricks for Comparision Based Questions

Duration: 11 min

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Inside: a video lesson and guided study material.

Module outline

  1. About the course: About the Course
  2. Mathematical Aptitude: संख्या पद्धति / Number System, महत्तम समापवर्तक और लघुत्तम समापवर्त्य / HCF and LCM, Divisibility Rules, प्रतिशत / Percentage, अनुपात और समानुपात / Ratio and Proportion, औसत / Average, लाभ, हानि और बट्टा / Profit, Loss and Discount, समय और कार्य / Time and Work, घन क्षेत्रमिति / Solid Mensuration, साधारण और चक्रवृद्धि ब्याज / Simple and Compound Interest, समय, चाल और दूरी / Time, Speed and Distance, Age Problems, मिश्रण और एलिगेशन / Mixture and Alligation, Algebra, सरलीकरण, घातांक और करणी / Simplification, Indices and Surds, Pipe and Cistern, Trigonometry, Statistics, आँकड़ा निर्वचन / Data Interpretation, Arithmetic, समुच्चय, संबंध, फलन और विविक्त गणित / Sets, Relations, Functions and Discrete Mathematics, संख्या पद्धति और संख्या सिद्धांत / Number Systems and Number Theory, निर्देशांक ज्यामिति, सदिश और त्रिविमीय ज्यामिति / Coordinate Geometry, Vectors and 3D Geometry, बहुपद, समीकरण और सम्मिश्र संख्याएँ / Polynomials, Equations and Complex Numbers
  3. Logical Reasoning: श्रेणी / Series, कूट लेखन एवं कूट वाचन / Coding-Decoding, सादृश्यता एवं वर्गीकरण / Analogy and Classification, रक्त संबंध / Blood Relations, दिशा एवं दूरी / Direction and Distance, क्रम एवं रैंकिंग / Order and Ranking, अशाब्दिक तर्क / Non-Verbal Reasoning, बैठक व्यवस्था एवं पहेलियाँ / Seating Arrangement and Puzzles, Syllogisms, वेन आरेख, न्याय वाक्य एवं असमानता / Venn Diagrams, Syllogism and Inequalities, गणितीय संक्रियाएँ एवं लुप्त संख्या / Mathematical Operations and Missing Numbers, वर्णमाला एवं संख्या परीक्षण / Alphabet and Number Test, कथन आधारित तार्किक विवेचन / Statement-Based Reasoning, Analytical Reasoning (Counting Figures Reasoning), घन, पासा एवं आकृतियों की गिनती / Cubes, Dice and Figure Counting, कैलेंडर एवं घड़ी / Calendar and Clock, Clock
  4. General Knowledge: वैज्ञानिक उपलब्धियाँ और अनुसंधान / Scientific Achievements and Research, Chemistry, Biology, History, Geography, Polity, Indian Economy, समसामयिकी / Current Affairs, Static General Knowledge
  5. Art of Teaching: शिक्षण-अधिगम प्रक्रिया एवं कक्षा प्रबंधन / Teaching-Learning Process and Classroom Management, Learners & Learning Process, Factors Affecting Teaching, शिक्षण विधियाँ एवं उपागम / Teaching Methods and Approaches, सूक्ष्म शिक्षण एवं कक्षा संप्रेषण / Microteaching and Classroom Communication, शिक्षण सहायक सामग्री एवं शैक्षिक तकनीकी / Teaching Aids and Educational Technology, आकलन एवं मूल्यांकन / Assessment and Evaluation, शिक्षक: गुण, व्यावसायिक नैतिकता एवं विकास / Teacher: Qualities, Professional Ethics and Development, शैक्षिक नीतियाँ, अधिनियम एवं प्रशासन / Educational Policies, Acts and Administration, पाठ्यचर्या, कला एवं सह-शैक्षिक क्षेत्र / Curriculum, Arts and Co-curricular Areas, निर्देशन एवं परामर्श / Guidance and Counselling, दिव्यांग बच्चों की शिक्षा / Education of Children with Disabilities, Micro-Teaching & Teaching Skills, पाठ योजना / Lesson Planning
  6. Environmental Science: Environment
  7. Unit 1 | Digital Electronics: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation
  8. Unit 2 | COA: Basics of COA, Floating Point Rep, Cache Memory Organization, Input Output Organisation, Instr Formats & Modes, Control Unit Design, Register Transfer and Microoperations, Programming the Basic Computer
  9. Unit 3 | C Programming: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
  10. Unit 3 | Data Structures: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
  11. Unit 4 | Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
  12. Unit 5 | Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management
  13. Unit 6 | Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Transaction Management, Concurrency Control
  14. Unit 7 | Computer Networks: 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
  15. Unit 8 | Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
  16. Unit 9 | Object Oriented Programming: OOPS with C++
  17. Unit 10 | Web Development: HTML Basics, CSS, JavaScript-Basics, XML, Node.js
  18. Unit 11 | Theory Of Computation: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Moore & Mealy Machines, Pushdown Automata & CFG, Turing Machines
  19. Unit 12 | IoT: Emerging Tech Trends, Cloud Computing, कंप्यूटर नेटवर्क / Computer Networks
  20. Unit 13 | Artificial Intelligence: Approaches to AI, Search Algorithms, Game Playing, Knowledge Representation, Natural Language Processing, Artificial Neural Networks, Genetic Algorithms
  21. Unit 14 | E-Commerce: Electronic Data Interchange and E-Commerce, Role of Internet and Web Services, Security in Mobile and Wireless Computing, Physical Security and Cryptography Basics, Cyber Safety and Security
  22. Unit 15 | Multimedia: Multimedia
  23. Unit 16 | Python: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis, DSA using Python
  24. Full Length Mock Tests — General Paper:
  25. Full Length Mock Tests — Computer Science (Paper II):
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This educational video is a lecture on solving time and work problems, a common topic in quantitative aptitude. The instructor, Yash Jain Sir, uses a digital whiteboard to present and solve three distinct problems. The first problem involves finding the time for 8 men and 12 women to complete a task, given the work rates of 4 men and 6 women in 5 days and 6 men and 4 women in 4 days. The instructor sets up equations using variables for the efficiency of a man (M) and a woman (W), equates the total work, and solves for the relationship between M and W. The second problem, from Wipro NLTH 2019, involves men and boys, where 6 men and 8 boys can complete a work in 10 days, and 26 men and 48 boys can do it in 2 days. The instructor uses a scaling method to find the work rate of 15 men and 20 boys. The third problem, from GATE ECE 2017, involves men and women building a bridge, with different combinations and timeframes. The instructor uses the concept of total work and equates the work done in different scenarios to find the number of men needed. The video concludes with a final problem on individual work rates, where the combined time for three people is calculated using the formula 1/(1/a + 1/b + 1/c). The overall teaching style is methodical, focusing on setting up equations and solving them step-by-step.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with a title card for a 'TIME & WORK' lecture. The instructor, Yash Jain Sir, introduces the first problem (Q1) on a digital whiteboard. The problem states: '4 Men and 6 Women can do a work in 5 days. 6 Men and 4 women can do the same work in 4 days. How many days will it take to complete the work if 8 men and 12 women work together?'. The instructor begins by defining the formula for total work as 'Men * Efficiency * No. of days'. He then assigns variables: 'Let efficiency of a man be M' and 'Let efficiency of a woman be W'. He starts writing the equation for the first scenario: 'Total Work = 4M * 5 = (4M + 6W) * 5'.

  2. 2:00 – 5:00 02:00-05:00

    The instructor continues to solve the first problem. He writes the equation for the second scenario: 'Total Work = 6M * 4 = (6M + 4W) * 4'. He then equates the two expressions for total work: '(4M + 6W) * 5 = (6M + 4W) * 4'. He expands both sides: '20M + 30W = 24M + 16W'. He simplifies the equation by moving terms: '30W - 16W = 24M - 20M', which becomes '14W = 4M'. He then solves for the relationship between M and W: 'M = 14W / 4 = 3.5W'. He then calculates the total work using the first scenario: 'Total Work = (4M + 6W) * 5'. He substitutes M with 3.5W: 'Total Work = (4*3.5W + 6W) * 5 = (14W + 6W) * 5 = 20W * 5 = 100W'.

  3. 5:00 – 10:00 05:00-10:00

    The instructor proceeds to find the time for 8 men and 12 women to complete the work. He calculates their combined efficiency: '8M + 12W'. He substitutes M with 3.5W: '8*3.5W + 12W = 28W + 12W = 40W'. He then uses the formula 'Time = Total Work / Combined Efficiency'. He substitutes the values: 'Time = 100W / 40W = 2.5 days'. He then moves to the second problem (Q2) from Wipro NLTH 2019, which states: '6 Men and 8 Boys can do a work in 10 days while 26 Men and 48 Boys can do the same work in 2 days. How many days will it take to complete the work if 15 men and 20 boys work together?'. He writes the first equation: '6M + 8B = 10 days'. He then multiplies this equation by 2.5 to get the work rate of 15 men and 20 boys: '15M + 20B = 10 / 2.5 = 4 days'. He then moves to the third problem (Q3) from GATE ECE 2017, which involves men and women building a bridge. He writes the first scenario: '1200 men and 500 women can build a bridge in 2 weeks'. He then writes the second scenario: '900 men and 250 women can build the bridge in 3 weeks'. He equates the total work: '(1200M + 500W) * 2 = (900M + 250W) * 3'. He expands both sides: '2400M + 1000W = 2700M + 750W'. He simplifies: '1000W - 750W = 2700M - 2400M', which becomes '250W = 300M'. He solves for W: 'W = 300M / 250 = 1.2M'. He then calculates the total work: 'Total Work = (1200M + 500W) * 2'. He substitutes W with 1.2M: 'Total Work = (1200M + 500*1.2M) * 2 = (1200M + 600M) * 2 = 1800M * 2 = 3600M'. He then calculates the time for 1200 men to build the bridge in one week: 'Time = Total Work / (1200M * 1) = 3600M / 1200M = 3 weeks'. He then moves to the final problem (Q4), which states: 'Manmohan Ji, Sonia Gandhi Ji and Kejriwal Ji can complete a piece of work in 24, 6 and 12 days respectively when they work alone. Working together, they will complete the same work in?'. He writes the formula for combined work rate: '1 / (1/24 + 1/6 + 1/12)'. He calculates the sum: '1/24 + 4/24 + 2/24 = 7/24'. He then calculates the time: '24/7 days'.

  4. 10:00 – 10:53 10:00-10:53

    The video concludes with a final problem on the screen. The problem states: 'Manmohan Ji, Sonia Gandhi Ji and Kejriwal Ji can complete a piece of work in 24, 6 and 12 days respectively when they work alone. Working together, they will complete the same work in?'. The instructor writes the formula for combined work rate: '1 / (1/24 + 1/6 + 1/12)'. He calculates the sum: '1/24 + 4/24 + 2/24 = 7/24'. He then calculates the time: '24/7 days'. The video ends with a 'THANKS FOR WATCHING' screen.

The video presents a structured and progressive lesson on solving time and work problems. It begins with a foundational problem that introduces the core concept of equating total work using variables for individual efficiencies. The instructor methodically demonstrates how to set up and solve equations to find the relationship between different work rates. The lesson then transitions to more complex problems, including those with different worker types (men/boys, men/women) and those requiring the calculation of combined work rates. The key methodological takeaway is the consistent application of the formula 'Total Work = Men * Efficiency * Time' and the strategic use of algebra to solve for unknowns. The video effectively uses a digital whiteboard to clearly illustrate each step of the problem-solving process, making it a valuable resource for students preparing for competitive exams.

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