Demo: Basics of Percentages, Percentage - Fraction Conversions

Duration: 13 min

This video lesson is available to enrolled students.

Return to /learn/RSSB-BASIC-COMPUTER-INSTRUCTOR/paper-1-basic-numeracy/percentage/conversion-between-fractions-ratio-percentages/asset-demo-basics-of-percentages-percentage-fraction-conversions after enrolling

Inside: a video lesson and guided study material.

Module outline

  1. About the Course: About the Course
  2. Paper-1 & 2 | Basic Numeracy: अनुपात और समानुपात / Ratio and Proportion, Divisibility Rules, मिश्रण और एलिगेशन / Mixture and Alligation, Permutation and Combination, Logarithm, संख्या पद्धति / Number System, महत्तम समापवर्तक और लघुत्तम समापवर्त्य / HCF and LCM, Sequence and Series (Series), समय, चाल और दूरी / Time, Speed and Distance, प्रतिशत / Percentage, औसत / Average, घन क्षेत्रमिति / Solid Mensuration, Age Problems, Arithmetic, Statistics, Probability, लाभ, हानि और बट्टा / Profit, Loss and Discount, साधारण और चक्रवृद्धि ब्याज / Simple and Compound Interest, Partnership, Speed Mathematics and Basic Mathematics, Algebra, सरलीकरण, घातांक और करणी / Simplification, Indices and Surds, समय और कार्य / Time and Work, Pipe and Cistern, RSSB Specific Videos - Basic Numeracy, 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. Paper-1 & 2 | Data Interpretation: आँकड़ा निर्वचन / Data Interpretation
  4. Paper-1 & 2 | General Mental Ability: Mental Ability, RSSB Specific Videos - Mental Ability
  5. Paper-1 & 2 | Logical Reasoning and Analytical Ability: श्रेणी / Series, कूट लेखन एवं कूट वाचन / Coding-Decoding, Data Sufficiency, अशाब्दिक तर्क / Non-Verbal Reasoning, Syllogisms, बैठक व्यवस्था एवं पहेलियाँ / Seating Arrangement and Puzzles, रक्त संबंध / Blood Relations, दिशा एवं दूरी / Direction and Distance, Analytical Reasoning (Counting Figures Reasoning), गणितीय संक्रियाएँ एवं लुप्त संख्या / Mathematical Operations and Missing Numbers, कैलेंडर एवं घड़ी / Calendar and Clock, Clock, घन, पासा एवं आकृतियों की गिनती / Cubes, Dice and Figure Counting, वेन आरेख, न्याय वाक्य एवं असमानता / Venn Diagrams, Syllogism and Inequalities, सादृश्यता एवं वर्गीकरण / Analogy and Classification, क्रम एवं रैंकिंग / Order and Ranking, कथन आधारित तार्किक विवेचन / Statement-Based Reasoning, Data Arrangement, वर्णमाला एवं संख्या परीक्षण / Alphabet and Number Test, Crypt Arithmetic
  6. Paper-1 & 2 | Decision Making and Problem Solving: आँकड़ों की पर्याप्तता एवं निर्णय क्षमता / Data Sufficiency and Decision Making
  7. Paper-1 | General Science: वैज्ञानिक उपलब्धियाँ और अनुसंधान / Scientific Achievements and Research, Biology, Chemistry, RSSB Specific Videos
  8. Paper-1 | General Awareness: राज्य विशेष सामान्य ज्ञान / State-Specific General Knowledge, समसामयिकी / Current Affairs
  9. Paper - 2 | Digital Logic Systems: Digital Systems & Boolean Basics, Logic Gates & Hardware, Combinational Circuit, Sequential Circuits
  10. Paper-2 | Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, Relational Calculus, Relational Algebra, SQL, NoSQL
  11. Paper-2 | Data Structures & Algorithms: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Algorithm Analysis, Sorting Algorithms, Intro to Compilers, Hashing
  12. Paper 2 | Data Communication and Network Security: Introduction to CN, Data Communication, Data Link Layer - Ethernet, DLL: Error Control, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Application Layer, Hardware basics, Network Security, Ethical Hacking
  13. Paper-2 | Operating Systems: Introduction to OS, Process Management, Memory Management, File Management, Deadlock
  14. Paper-2 | Computer Organization and Architecture: 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, Number System, Number Representation
  15. Paper 2 | System Analysis and Design: Fundamentals of Systems and Information Systems, Fundamentals of Software Engineering, SDLC and Development Approaches, Software Documentation and Software Requirements Specification (SRS), SDD and Quality Assurance, Security, Risk Management & Maintenance, Software Testing
  16. Paper-2 | C Programming: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
  17. Paper 2 | OOPS , C++ , JAVA: Language Design, OOPS with C++, Java, .Net Programming, Java Fundamentals
  18. Paper 2 | Python: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis
  19. Emerging Trends and AI: Emerging Tech Trends, कंप्यूटर के मूल सिद्धांत / Computer Fundamentals, व्यापार, विपणन एवं उपभोक्ता संरक्षण / Trade, Marketing and Consumer Protection
  20. Paper-2 | Data Processing (Ms-Office): MS Office Applications, कंप्यूटर सॉफ़्टवेयर / Computer Software, ऑपरेटिंग सिस्टम / Operating System, वर्ड प्रोसेसिंग (MS Word) / Word Processing (MS Word), प्रेज़ेंटेशन (MS PowerPoint) / Presentation Software (MS PowerPoint)
  21. Paper-2 | Internet and Web Technologies: HTML Basics, CSS, XML, JavaScript-Basics, Internet Fundamentals, Protocols & Services, Web Publishing & Hosting, Server Side & Security, Emerging Technologies, Terms & Abbreviations, Cyber Threats and Malware Attacks, Role of Internet and Web Services, Security in Mobile and Wireless Computing, साइबर सुरक्षा / Cyber Safety and Security, कंप्यूटर नेटवर्क / Computer Networks
  22. Paper 2 | Pedagogy: वृद्धि और विकास / Growth and Development, विकास के सिद्धांत / Theories of Development, Concept of Pedagogy, समावेशी शिक्षा / Inclusive Education, Experiential Pedagogy, आकलन और मूल्यांकन / Assessment and Evaluation, संज्ञानात्मक प्रक्रियाएँ / Cognitive Processes, समाजीकरण और जेंडर / Socialisation and Gender, National Education Policy (NEP) 2020
  23. Live Classes: RSSB Live Sessions
  24. Paper 1 - Full Mock Tests:
  25. Paper 2 - Full Mock Tests:
  26. BCI Previous Year Papers:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This educational video lecture, presented by Yash Jain, provides a comprehensive introduction to the fundamentals of percentages and their conversion into fractions. The lesson begins by establishing the core conceptual understanding of a percentage as a value per hundred, using practical examples like discounts to illustrate how 25% represents Rs. 25 off every Rs. 100 of price. The instructor systematically scales this logic to higher values such as Rs. 200 and Rs. 300, demonstrating proportional calculations for various items including T-shirts and pants. The curriculum then transitions to real-world applications, covering shopping mall discounts, academic marks, population changes, and company performance metrics. A significant portion of the lecture is dedicated to mathematical conversions, specifically teaching how to convert percentages into fractions by dividing by 100 and simplifying the result. This includes handling complex cases involving mixed fractions like 16 + (2/3)% and 83 + (1/3)%. The final segment introduces an important property of percentages, deriving the formula for calculating P% of X as (P/100) * X. The instructor demonstrates this property through step-by-step calculations, such as finding 20% of 800 and comparing A% of B with B% of A, effectively bridging the gap between conceptual understanding and computational application.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The lecture opens with a title slide introducing the topic of Percentages by Yash Jain, setting the stage for the lesson. The instructor immediately moves to basic concepts, posing a critical question: 'What does a discount of 25% mean?' The core definition is established on-screen stating that for every Rs. 100 price, a customer receives a discount of Rs. 25. This foundational concept is reinforced by calculating the net price for a reference value of Rs. 100, showing the subtraction '100 - 25'. The instructor then scales this logic to demonstrate proportional discounts for higher price points, specifically calculating the discount for Rs. 200 as Rs. 50 and for Rs. 300 as Rs. 75, visually displaying the arithmetic '200 - 50' and '300 - 75' to solidify the understanding of percentage as a rate per hundred.

  2. 2:00 – 5:00 02:00-05:00

    Building on the base reference of Rs. 100, the instructor applies the discount concept to a handwritten table listing specific items with varying prices. The visible text shows calculations for a T-shirt priced at 300 (discount 75), Pants at 400 (discount 100), Lower at 200 (discount 50), and Hand gloves at 100 (discount 25). This practical application transitions into a broader discussion on the applications of percentages, with text on screen listing 'Shopping Mall Discounts', 'Marks' (80%, 70%, 60%), and 'Increase or decrease in performance or population'. The instructor demonstrates calculating specific percentage values, such as 30% of 200 resulting in 60 and 30% of 100 resulting in 30. The segment concludes by introducing the rules for converting percentages into fractions, explicitly writing 'Percentage to Fraction (Divide by 100)' and 'Fraction to Percentage (Multiply by 100)' on the board.

  3. 5:00 – 10:00 05:00-10:00

    This segment focuses on the mechanical process of converting percentages to fractions using specific examples. The instructor solves 25% by writing '25/100' and simplifying it to '1/4'. Similarly, 60% is converted to '60/100', simplified to '3/5', and expressed as a ratio '3:5'. The lesson advances to handling mixed fraction percentages, starting with 16 + (2/3)%. The instructor converts the mixed number to an improper fraction '50/3', divides by 100, and simplifies the result to '1/6'. A new example is introduced at the end of this window involving 83 + (1/3)%, where the mixed number is converted to '250/3' before division by 100. The visual evidence shows the step-by-step reduction of these complex fractions, emphasizing the rule to convert mixed numbers to improper fractions first before applying the division by 100 rule.

  4. 10:00 – 12:43 10:00-12:43

    The final section introduces 'An Important Property of Percentages', deriving the general formula for calculating P% of X as (P/100) * X, which simplifies to PX/100. The instructor demonstrates this with a specific calculation of '20% of 800', showing the conversion to '20/100 * 800' and arriving at the result '160'. The lesson concludes by presenting a comparative property on screen: 'A% of B' versus 'B% of A', using the example '75% of 32' and '32% of 75'. The video ends with a closing slide displaying the text 'THANKYOU FOR WATCHING', marking the conclusion of the instructional content on percentage and fraction conversions.

The lecture effectively progresses from conceptual definitions to computational fluency. The teaching strategy relies heavily on the 'per hundred' baseline, using Rs. 100 as a constant reference to explain discounts before scaling to arbitrary numbers like 200 or 300. This scaffolding allows students to grasp the proportional nature of percentages before tackling abstract calculations. The transition from practical applications like shopping discounts and marks to formal mathematical conversions (percent to fraction) is logical, ensuring students understand the utility of percentages in real life before mastering the arithmetic. The handling of mixed fractions like 16 + (2/3)% is a critical technical skill emphasized, requiring the conversion to improper fractions before division. The final property of percentages (A% of B = B% of A) serves as a powerful shortcut for mental math, rounding out the lesson with both fundamental rules and advanced properties. The consistent use of on-screen text to display formulas like 'P/100 * X' and specific calculations ensures that the visual evidence supports the verbal instruction, making it suitable for revision notes.

Loading lesson…