Short Tricks to deal with cases of 'At least' & 'At most'

Duration: 9 min

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Module outline

  1. General Intelligence & Reasoning: Analogy, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Blood Relations, Directions (Direction Test), Ranking, Order and Sequence, Logical Sequence Of Words, Syllogisms, Venn Diagram, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Selection Decision Table (Decision Making), Data Sufficiency, Puzzle Solving (Puzzles), Data Arrangement, Cubes & Dices, Calendar, Clock, Arithmetic, Number System, HCF LCM, Verbal Analogy (Word Based Analogy), Visual Recognition and Figure Completion, Paper Folding and Cutting, Transformation of Shapes, Clocks and Calendars, Direction Sense, Cubes and Dice, Patterns in Two-Dimensional Figures, Seating Arrangements, Analogy and Classification, Logical Deduction and Induction, Alphabet and Word Tests, Mathematical Operations, Series Completion, Simplification and Approximation, Coding and Decoding, Numerical Reasoning, Assembling and Grouping of Shapes, Three-Dimensional Patterns and Visualization, Vocabulary, Number System, Averages, Mixtures and Alligation, Simple and Compound Interest, Percentages, Algebra, Speed, Time and Distance, Seating and Arrangement Puzzles, Traverse Surveying, Order, Ranking and Sequence, Constraint Puzzles, Syllogisms and Venn Diagrams, Reading Comprehension, Critical Reasoning, Permutations and Combinations, Narrative Sequencing, Project Monitoring, Resources and Safety, Profit, Loss and Discount, Ratio and Proportion, Time and Work, Mensuration, Data Interpretation, Powers, Surds and Logarithms, Sequences and Series, Articles and Determiners, Sentence Completion, Data Sufficiency, Blood Relations, Simple Interest and Compound Interest, Mixture and Alligation, Sequence and Series (Series), Speed Time and Distance, Algebra, Profit and Loss, Powers and Exponents (Surds and Indices), Permutation and Combination
  2. General Awareness: Physics, Chemistry, Biology, History, Geography, Polity, Indian Economy, Environment, Static General Knowledge, GK- Current Affairs, Artificial Intelligence, MS Office Applications, Terms & Abbreviations, Keyboard Shortcuts, Evolution of Indian Banking (Banking & Financial Awareness), Emerging Tech Trends
  3. Engineering Mathematics: Set Theory, Relations, Functions, Graph Theory, Group Theory, Propositional and Predicate Logic, Linear Algebra, Calculus, Probability, Statistics, Signal Space and Optimum Detection, Probability, Statistics
  4. Digital Logic: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Floating Point Rep, Number Systems and Codes, Registers and Counters, Boolean Algebra and Logic Gates, Microprocessors and Microcontrollers, Logic Families and CMOS Logic, Microprocessors, Logic Gates and Boolean Algebra, Minimization of Boolean Functions, Timing, Hazards and Testing, Logic Families, Combinational Logic Design, Arithmetic Circuits, Waveform Generators and Timer Circuits, Semiconductor Memories and Programmable Logic Devices, Combinational Logic Circuits, Latches and Flip-Flops, Finite State Machines, Sequential Circuits and State Machines, Minimization of Boolean Functions, Arithmetic Circuits, Latches and Flip-Flops, Number Systems and Codes, Registers and Counters
  5. Computer Organisation & Architecture: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Programming the Basic Computer, Register Transfer and Microoperations, Semiconductor Memories and Programmable Logic, Processor Organization and Instructions, Memory Hierarchy and Input/Output, Registers and Counters
  6. Programming & Data Structures: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, HTML Basics, OOPS with C++, Java, Object Oriented Technology
  7. Databases: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Relational Calculus, Transaction Management, Concurrency Control, Database Recovery, Database Security & Authorization
  8. Algorithms: Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos
  9. Theory of Computation: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Moore & Mealy Machines, Pushdown Automata & CFG, Turing Machines, Complexity Theory
  10. Compiler Design: 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
  11. Operating System: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Threads & Process Creation, Deadlock, Memory Management, Virtual Memory, Disc Scheduling, File Management, Security, Windows OS, Distributed Systems, Unix OS, Linux OS
  12. Computer Networks: Introduction to CN, 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, Data Communication, Website, Browser & Services, Web Design & Development, Network Security, Cyber Threats and Malware Attacks, Cyber Safety and Security
  13. Full Length Mock Tests:
  14. Sectional Tests:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This educational video, presented by Yash Jain from Knowledge Gate, provides a step-by-step solution to a probability problem. The core of the lesson is the calculation of probabilities for different outcomes when a coin is tossed twice. The instructor begins by defining the sample space, which consists of four equally likely outcomes: HH, HT, TH, and TT. He then systematically addresses three parts of the question: (i) the probability of getting exactly one head, (ii) the probability of getting at least one head, and (iii) the probability of getting at most one head. For each part, he identifies the favorable outcomes from the sample space and applies the fundamental formula for probability: P(E) = (Number of favorable outcomes) / (Total number of outcomes). The video demonstrates the direct calculation method and also shows how to use the complement rule for part (ii), where P(at least one head) = 1 - P(no heads). The visual presentation uses a digital whiteboard with handwritten text and diagrams to clearly illustrate the problem-solving process.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with a title slide featuring the word "PROBABILITY" in a purple box, surrounded by four images: a casino table with dice, a basket of fruit, a pizza box, and a business meeting. The scene then transitions to the main lecture slide, which has a pink background with a word cloud. The title "PROBABILITY" is displayed at the top, and the instructor, Yash Jain, is shown in a small window in the bottom right corner. The slide introduces the problem: "A coin is tossed twice. Find the probability of getting:" followed by three sub-questions: (i) exactly one head, (ii) at least one head, and (iii) at most one head. The instructor begins to explain the problem, and the on-screen text clearly states the question and its parts.

  2. 2:00 – 5:00 02:00-05:00

    The instructor begins to solve the problem by first defining the sample space. On the digital whiteboard, he writes "Total = {HH, HT, TH, TT}" to list all possible outcomes of two coin tosses. He then explains that the total number of outcomes is 4. For part (i), "exactly one head," he identifies the favorable outcomes as {HT, TH}. He writes "(i) Fav outcome = {HT, TH}" and calculates the probability as P(i) = 2/4 = 1/2. For part (ii), "at least one head," he identifies the favorable outcomes as {HH, HT, TH}, writing "(ii) 1 Head OR 2 Head = {HH, HT, TH}". He calculates P(ii) = 3/4. The instructor uses a red pen to write all the text and equations on the screen, making the process clear and easy to follow.

  3. 5:00 – 8:33 05:00-08:33

    The instructor moves to part (iii), "at most one head." He defines the favorable outcomes as {HT, TH, TT}, writing "(iii) 0 Head OR 1 Head = {HT, TH, TT}". He calculates the probability as P(iii) = 3/4. He then demonstrates an alternative method for part (ii) using the complement rule. He writes "P(E') = 1 - P(E)" and identifies the event E as "at least one head." The complement E' is "no head," which corresponds to the outcome {TT}. He calculates P(E') = 1/4 and then P(E) = 1 - 1/4 = 3/4, confirming the result from the direct method. The video concludes with a final screen that says "THANKS FOR WATCHING".

The video presents a clear and structured lesson on calculating probabilities for compound events. It begins by establishing the sample space for a simple experiment (two coin tosses) and then applies the basic probability formula to three different, related events. The instructor effectively uses both direct enumeration of favorable outcomes and the complement rule, demonstrating two essential problem-solving strategies. The visual aid of the digital whiteboard allows for a step-by-step walkthrough, making the logical progression from problem statement to solution easy to follow. The lesson reinforces the fundamental concept that probability is the ratio of favorable outcomes to the total number of possible outcomes.

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