Divisibility Rules of 17 and 18

Duration: 12 min

This video lesson is available to enrolled students.

Return to /learn/RSSB-BASIC-COMPUTER-INSTRUCTOR/paper-1-basic-numeracy/divisibility-rules/divisibility-rules-for-all-numbers/asset-divisibility-rules-of-17-and-18 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 provides a comprehensive lesson on divisibility rules, focusing on the number 17 and concluding with the rule for 18. The video begins with a title card and a colorful, circular diagram summarizing various divisibility rules. The main content is delivered by an instructor, Yash Jain, who explains three distinct methods for testing divisibility by 17. The first method involves subtracting five times the last digit from the remaining number, with an example demonstrating the process for 3978. The second method, introduced later, is to subtract the last two digits from two times the rest of the number, illustrated with the example 4675. The third method is to add nine times the last digit to five times the rest of the number, with examples including 4675 and 238. The video concludes with the divisibility rule for 18, which states a number is divisible by 18 if it is divisible by both 2 and 9, demonstrated with the number 342. The presentation uses a digital whiteboard for calculations and includes a copyright notice from Knowledge Gate Eduventures.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with a title card displaying 'DIVISIBILITY RULES' over a background of scattered numbers. This transitions to a colorful, circular diagram titled 'DIVISIBILITY RULES' which visually summarizes rules for divisibility by 2, 3, 4, 5, 6, 8, 9, 10, and 11. The instructor, Yash Jain, appears in a small window, introducing the topic. The main content begins with a slide titled 'Test for divisibility by 17,' which states the rule: 'Subtract five times the last digit from the remaining leading truncated number. If the result is divisible by 17, then so was the first number. Apply this rule over and over again as necessary.' An example is provided: '3978 --> 397 - 5*8 = 357 --> 35 - 5*7 = 0. So 3978 is divisible by 17.' The instructor begins to explain this rule, and the number 3978 is written on the board.

  2. 2:00 – 5:00 02:00-05:00

    The instructor demonstrates the divisibility test for 17 on the number 3978. He first identifies the last digit as 8 and calculates 5 times 8, which is 40. He then subtracts 40 from the remaining number, 397, to get 357. The process is repeated: the last digit of 357 is 7, and 5 times 7 is 35. Subtracting 35 from 35 gives 0. Since 0 is divisible by 17, the original number 3978 is also divisible by 17. The instructor uses a digital whiteboard to write out each step of the calculation, including the subtraction of 40 from 397 and the subsequent steps, clearly showing the process of reducing the number until a final result is reached.

  3. 5:00 – 10:00 05:00-10:00

    The video introduces a second divisibility rule for 17. The slide is titled 'Divisibility Rule of 17' and states: 'Subtract the last two digits from two times the rest.' An example is given: '4,675: 46 x 2 - 75 = 17.' The instructor demonstrates this with the number 4675. He takes the first part, 46, multiplies it by 2 to get 92, then subtracts the last two digits, 75, to get 17. Since 17 is divisible by 17, the original number is divisible by 17. The instructor then introduces a third rule: 'Add 9 times the last digit to 5 times the rest. Drop trailing zeroes.' Examples are provided: '4,675: 467 x 5 + 5 x 9 = 2380' and '238: 23 x 5 + 8 x 9 = 187.' He begins to work through the first example, calculating 467 x 5 and 5 x 9, and then adding the results.

  4. 10:00 – 12:14 10:00-12:14

    The instructor continues to demonstrate the third divisibility rule for 17. He completes the calculation for 4675, showing that 467 x 5 = 2335 and 5 x 9 = 45, which sum to 2380. He then applies the rule to 238, calculating 23 x 5 = 115 and 8 x 9 = 72, which sum to 187. The video then transitions to the divisibility rule for 18. The slide states: 'It is divisible by 2 and by 9.' An example is given: '342: it is divisible by 2 and by 9.' The instructor demonstrates this by checking if 342 is even (divisible by 2) and then summing its digits: 3 + 4 + 2 = 9, which is divisible by 9. The video concludes with a 'THANKS FOR WATCHING' screen.

The video systematically teaches three different methods for determining if a number is divisible by 17, each offering a unique approach to simplify the problem. The first method uses subtraction, the second uses a combination of multiplication and subtraction, and the third uses addition. This progression demonstrates that complex divisibility rules can be broken down into manageable steps. The lesson concludes with a standard rule for 18, reinforcing the concept that a number can be divisible by a composite number if it is divisible by its prime factors. The clear, step-by-step demonstrations on a digital whiteboard make the abstract rules concrete and easy to follow.

Loading lesson…