Practice Question

Duration: 11 min

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Module outline

  1. Quantitative Aptitude: Ratio and Proportion (Ratios), Data Interpretation, Mixture and Alligation, Permutation and Combination, Number System, Sequence and Series (Series), Speed Time and Distance, Speed Mathematics and Basic Mathematics, Algebra, Percentage, Profit and Loss, Simple Interest and Compound Interest, Powers and Exponents (Surds and Indices), Time and Work, Mensuration and Geometry, Partnership
  2. Reasoning Ability: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Seating Arrangements, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Directions (Direction Test), Ranking, Order and Sequence, Syllogisms, Blood Relations, Puzzle Solving (Puzzles), Inequality, Machine Input-Output
  3. English Language: Vocabulary, Noun, Subject Verb Agreement (Verb Noun Agreement), Adjectives, Tenses, Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Cloze Test (Cloze Passage), Sentence Correction (Error Correction), Sentence Completion (Fill in the blanks), Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Sentence Construction, Pronoun, Preposition, Conjunction, Adverb, Verb, Modals, Articles, Determiner, Interjection
  4. General Awareness: Evolution of Indian Banking (Banking & Financial Awareness), GK- Current Affairs, Static General Knowledge, Indian Economy
  5. C Concepts + MCQs (IT Specialist): C Programming by Yash Sir, C Language Core
  6. Java (IT Specialist): Java
  7. Python (IT Specialist): Python for Placements by Yash Sir, Python Basics
  8. OOPs (IT Specialist): Object Oriented Programming (OOPS)
  9. DBMS (IT Specialist): Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, Relational Calculus, Transaction Management, Concurrency Control, Database Recovery, ORDBMS, Database Security & Authorization, Query Processing & Optimization, Enhanced Data Models, Data Warehousing & Mining, Big Data Systems, NoSQL
  10. SQL (IT Specialist): SQL
  11. Software Engineering (IT Specialist): Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
  12. Data Structure (IT Specialist): Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
  13. Operating System (IT Specialist): Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Deadlock, Threads & Process Creation, Memory Management, Virtual Memory, Disc Scheduling, File Management, Windows OS, Linux OS, Security, Distributed Systems, Virtual Machines
  14. Compiler Design (IT Specialist): Intro to Compilers, Lexical Analysis, Grammar & CFG, Syntax Analysis: Top-Down, Syntax Analysis: Bottom-Up, Semantic Analysis & SDT, Intermediate Code Gen, Code Optimization, Run Time Environment
  15. Computer Architecture (IT Specialist): Basics of COA, Floating Point Rep, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Register Transfer and Microoperations, Multiprocessors, Programming the Basic Computer
  16. Data Communication & Networking (IT Specialist): 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, Hardware basics, Network Security
  17. Descriptive Test (Main Exam): English Writing Ability
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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