Practice Question

Duration: 11 min

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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 lecture demonstrates how to calculate Average Turnaround Time (TAT) and Average Waiting Time (WT) using the First Come First Serve (FCFS) scheduling algorithm. The instructor works through two practice problems on a whiteboard, using a table with columns for Process Number, Arrival Time (AT), Burst Time (BT), Completion Time (CT), TAT = CT - AT, and WT = TAT - BT. For the first problem, processes P0 (AT 0, BT 3), P1 (AT 2, BT 2), and P2 (AT 6, BT 4) are scheduled in arrival order. A Gantt chart shows P0 running from 0 to 3, P1 from 3 to 5, an idle gap from 5 to 6, and P2 from 6 to 10. Completion times are 3, 5, and 10, giving TAT values of 3, 3, and 4, and WT values of 0, 1, and 0. The instructor writes Avg TAT = 10/3 and Avg Waiting Time = 1/3. A second problem uses processes with AT 0, 0, 1 and BT 4, 6, 3. The Gantt chart shows P0 from 0 to 4, P1 from 4 to 10, and P2 from 10 to 13, with CT values 4, 10, 13, TAT values 4, 10, 12, and WT values 0, 4, 9. The instructor writes Avg TAT = 24/3 and Avg WT = 13/3. Ready and Run state diagrams are used to track which processes are waiting and which is executing.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The whiteboard displays the question: 'Calculate the Average Turnaround Time (TAT) and Average Waiting Time (WT) using the FCFS (First Come First Serve) Scheduling Algorithm.' A table is set up with columns P. No, Arrival Time (AT), Burst Time (BT), Completion Time (CT), TAT = CT - AT, and WT = TAT - BT. Rows show P0 (AT 0, BT 3), P1 (AT 2, BT 2), P2 (AT 6, BT 4), and an empty Average row. The instructor begins drawing a green Gantt chart below the table and labels Ready and Run states in a diagram.

  2. 2:00 – 5:00 02:00-05:00

    The instructor builds the Gantt chart for the first problem: P0 runs from 0 to 3, P1 from 3 to 5, an idle gap is marked in red from 5 to 6, and P2 runs from 6 to 10. Time markers 3, 5, and 6 are written beneath the chart. He then fills the table with pink values: CT 3, 5, 10 and TAT 3, 3, 4. Red checkmarks and circles mark the AT values 0, 2, 6 and BT values 3, 2, 4, confirming the input data before computing derived columns.

  3. 5:00 – 10:00 05:00-10:00

    The instructor completes the first problem by writing Avg Waiting Time = 1/3 and Avg TAT = 10/3 on the right side of the board, alongside Ready and Run circles containing P0, P1, P2. He then introduces a second problem with a new table headed Prd, AT, BT, CT, TAT, WT showing arrival values 0, 0, 1 and burst values 4, 6, 3. He sketches a green Gantt bar and a two-circle diagram labeled 'Ready P0, P1' and 'Run' with a magenta 'FCFS' label, circling the zero arrival entries for P0 and P1.

  4. 10:00 – 11:01 10:00-11:01

    The second problem is completed on the board. The table shows CT values 4, 10, 13 and a TAT-BT/WT column listing 0, 4, 9. The instructor writes Avg TAT = 24/3 and Avg WT = 13/3. A green Gantt chart at the bottom displays P0, P1, P2 with time markers 4, 10, 13, confirming the execution order P0 (0-4), P1 (4-10), P2 (10-13).

The lecture teaches FCFS scheduling through two worked examples. The method is: (1) list processes by arrival time; (2) draw a Gantt chart showing execution order, including idle gaps when no process is ready; (3) compute CT from the Gantt chart; (4) compute TAT = CT - AT; (5) compute WT = TAT - BT; (6) average TAT and WT across all processes. Key evidence: first problem yields CT 3, 5, 10; TAT 3, 3, 4; WT 0, 1, 0; Avg TAT = 10/3; Avg WT = 1/3. Second problem yields CT 4, 10, 13; TAT 4, 10, 12; WT 0, 4, 9; Avg TAT = 24/3; Avg WT = 13/3. The Ready/Run diagram helps track which processes are waiting versus executing. Idle time in the Gantt chart (e.g., 5 to 6 in the first problem) does not contribute to any process's execution but affects completion times of later processes.

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