Tricks to Solve Grouping Type Questions in P&C

Duration: 12 min

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Inside: a video lesson and guided study material.

Module outline

  1. About the Course: About the Course
  2. Section 1 | Language (Hindi): भाषा, लिपि, ध्वनि, वर्ण, अक्षर, स्वर, व्यंजन, मात्रा और संयुक्ताक्षर, वर्तनी, वर्ण-विन्यास, अनुस्वार, अनुनासिक, चंद्रबिंदु और ‘र’ के रूप, शब्द, पद और शब्द-भेद, संज्ञा और सर्वनाम, विशेषण और क्रिया, लिंग, वचन, पुरुष और कारक, काल, वाच्य, वाक्य और वाक्य-भेद, संधि, समास, विलोम शब्द, पर्यायवाची शब्द, सामान्य अशुद्धियाँ, अनेक शब्दों के लिए एक शब्द, मुहावरे और लोकोक्तियाँ, अपठित गद्यांश और अपठित पद्यांश, Multi-Topic Content (Cross-Concept Material), वर्णमाला
  3. Section 1 | Language (उर्दू भाषा — 22 प्रश्न (निश्चित)): Spelling & Diacritics, Grammar (اسم, فعل, صفت, ضمیر), Vocabulary, Idioms & Proverbs, Comprehension
  4. Section 1 | Language (বাংলা / बांग्ला भाषा — 22 प्रश्न (निश्चित)): Bangla Script and Sounds, Bangla Grammar and Usage, Bangla Word Formation and Vocabulary, Reading and Text Interpretation
  5. Section 1 | Language (English): Vocabulary, Noun, Subject Verb Agreement (Verb Noun Agreement), Adjectives, Tenses, Pronoun, Verb, Adverb, Preposition, Articles, Determiner, Conjunction, Modals, Active Passive Voice (Voice), Direct and Indirect Speech, Sentence Correction (Error Correction), Sentence Completion (Fill in the blanks), Sentence Construction, Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Cloze Test (Cloze Passage), Verbal Analogy (Word Based Analogy), Facts, Inference and Judgements
  6. Section 2 | Primary Maths & Reasoning: Ratio and Proportion (Ratios), Divisibility Rules, Mixture and Alligation, Permutation and Combination, Number System, HCF LCM, Sequence and Series (Series), Speed Time and Distance, Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Percentage, Average, Profit and Loss, Simple Interest and Compound Interest, Time and Work, Mensuration and Geometry, Age Problems, Arithmetic, Powers and Exponents (Surds and Indices), Algebra, Probability, Trigonometry, Syllogisms, Seating Arrangements, Blood Relations, Directions (Direction Test), Analytical Reasoning (Counting Figures Reasoning), Puzzle Solving (Puzzles), Calendar, Clock, Cubes & Dices, Venn Diagram, Data Arrangement, Inequality, Analogy, Ranking, Order and Sequence
  7. Section 2 | General Awareness (GK + Current Affairs): Polity, Physics, Biology, State Wise GK, Chemistry, History, Geography, Indian Economy, Environment, GK- Current Affairs, Static General Knowledge
  8. Section 3 | Computer System and Org. (CSO): Basics of COA, Floating Point Rep, Cache Memory Organization, Instr Formats & Modes, Programming the Basic Computer, Input Output Organisation, Register Transfer and Microoperations, Control Unit Design
  9. Section 3 | Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, SQL, File Organization & Indexing, Relational Algebra, Relational Calculus, Transaction Management, Concurrency Control
  10. Section 3 | Operating System: Introduction to OS, Process Management, CPU Scheduling, Threads & Process Creation, Memory Management, Virtual Memory, Disc Scheduling, File Management, Process Synchronization
  11. Section 3 | Computer Networks: Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, DLL: Error Control, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware basics
  12. Section 3 | Data Structures: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Minimum Spanning Trees, Shortest Path Algos
  13. Section 3 | Theory Of Computation & Compiler Design: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Moore & Mealy Machines, Pushdown Automata & CFG, Turing Machines, Intro to Compilers, Lexical Analysis, Grammar & CFG, Syntax Analysis: Top-Down, Syntax Analysis: Bottom-Up, Semantic Analysis & SDT, Intermediate Code Gen, Code Optimization
  14. Section 3 | Emerging Trends (AI, Societal Ethics & MS Office): Artificial Intelligence, Emerging Tech Trends, Society, Law & Ethics, MS Office Applications
  15. Section 3 | Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Maintenance and Configuration Management, Software Testing
  16. Section 3 | C Programming: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling
  17. Section 3 | OOPS, C++, JAVA, HTML: OOPS with C++, Java, HTML Basics, CSS
  18. Section 3 | Java: Java Fundamentals, Array, String, IO & References
  19. Section 3 | Python: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis
  20. Section 3 | Digital Electronics: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation
  21. Section 3 | Multimedia: Multimedia
  22. BPSC Previous Year Papers:
  23. BPSC Full Mock Tests:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This educational video is a lecture on permutations and combinations, presented by an instructor from Knowledge Gate Educator. The video begins with a title slide that visually distinguishes between permutations and combinations using examples like a dice game and a fruit basket. The main content starts with a problem: "In how many ways can we arrange 4 boys and 5 girls?" The instructor explains that this is a permutation problem because the order of arrangement matters. He calculates the total number of arrangements as 9! (362,880), representing the permutation of 9 distinct individuals. The lecture then transitions to a more complex problem involving 5 boys and 4 girls, with four different constraints: (a) no two girls are together, (b) no two boys are together, (c) a particular pair of girls always sits together, and (d) a particular pair of girls do not sit together. For each case, the instructor uses the fundamental principles of permutations, including treating a group as a single unit and applying the formula nPk = n! / (n-k)!. The video concludes with a final 'Thanks for Watching' screen.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with a title slide that introduces the topic of permutations and combinations. The slide is divided into four quadrants: the top-left shows a dice game, the top-right shows a fruit basket, the bottom-left shows a pizza, and the bottom-right shows two people in an office. The words "PERMUTATION" and "COMBINATION" are prominently displayed. The scene then transitions to a presentation slide titled "Confused" with the question "Should I unlock with Permutation or Combination?". This slide features a cartoon detective character and two lockboxes labeled "Permutation" and "Combination". The instructor, Yash Jain, is visible in a small window in the bottom right corner. The slide also includes the branding for "Knowledge Gate Educator" and the text "Basic To Advance".

  2. 2:00 – 5:00 02:00-05:00

    The video displays a problem on a yellow background with a pattern of small shapes. The problem is: "q: In how many ways can we arrange 4 boys and 5 girls?" The instructor begins to solve this by identifying the total number of students as 9. He explains that since the question is about arranging people, the order matters, which makes it a permutation problem. He writes the formula for the total number of arrangements as 9!, which he calculates as 362,880. He also notes that the arrangement of the 4 boys is 4! and the arrangement of the 5 girls is 5!, but clarifies that for the total arrangement of all 9 individuals, it is simply 9!.

  3. 5:00 – 10:00 05:00-10:00

    The video presents a new problem: "q: 5 Boys and 4 Girls" with four sub-questions. The instructor begins to solve the first part, (a) "No two girls are together". He explains that to ensure no two girls are together, the boys must be arranged first, creating spaces between them where the girls can be placed. He writes the arrangement of 5 boys as B1 B2 B3 B4 B5, which creates 6 possible spaces (before, between, and after the boys). He then explains that the 4 girls must be placed in 4 of these 6 spaces, which is a permutation of 6 items taken 4 at a time, written as 6P4. He calculates this as 6! / (6-4)! = 6! / 2! = 360. He then multiplies this by the number of ways to arrange the 5 boys, which is 5!, to get the total number of arrangements for this condition.

  4. 10:00 – 12:22 10:00-12:22

    The instructor continues to solve the remaining parts of the problem. For part (b) "No two boys are together", he explains that the girls must be arranged first, creating spaces for the boys. He writes the arrangement of 4 girls as G1 G2 G3 G4, which creates 5 spaces. He then calculates the number of ways to place 5 boys in these 5 spaces as 5P5, which is 5!. He multiplies this by the number of ways to arrange the 4 girls, which is 4!, to get the total. For part (c) "Particular pair of girls always sit together", he treats the pair as a single unit, so there are 8 items to arrange (the pair and the other 7 individuals). He calculates the number of arrangements as 8! and multiplies it by 2! (the number of ways the pair can be arranged within their unit). For part (d) "A particular pair of girls do not sit together", he explains that this is the total number of arrangements minus the number of arrangements where the pair sits together. He writes the formula as #total - #sit together, which is 9! - (8! x 2!). The video ends with a black screen that says "THANKS FOR WATCHING".

The video provides a structured and progressive lesson on permutations and combinations. It begins by establishing the fundamental difference between the two concepts using visual metaphors. The core of the lesson is a series of worked examples that build in complexity. The first example is a straightforward permutation of 9 distinct individuals. The second example, involving 5 boys and 4 girls, systematically applies the principles of permutations to solve four different constrained arrangement problems. The instructor demonstrates key problem-solving techniques, such as treating a group as a single unit and using the principle of subtraction to find the number of arrangements where a condition is not met. The progression from simple to complex problems effectively reinforces the core concepts of permutation and combination.

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