Part 6 - Important Practice Questions

Duration: 9 min

This video lesson is available to enrolled students.

Return to /learn/WIPRO-PREPARATION/logical-reasoning/data-sufficiency/algebra-and-exponent-based-data-sufficiency/asset-part-6-important-practice-questions after enrolling

Inside: a video lesson and guided study material.

Module outline

  1. Quantitative Aptitude: Number System, Percentage, Profit and Loss, Ratio and Proportion (Ratios), Average, Time and Work, Speed Time and Distance, Simple Interest and Compound Interest, Mixture and Alligation, Data Interpretation, Permutation and Combination, Probability, Logarithm, Powers and Exponents (Surds and Indices), Age Problems, Divisibility Rules, Partnership, HCF LCM, Algebra, Pipe and Cistern
  2. Logical Reasoning: Series (Number and Letter Series) (Numerical Relations and Reasoning), Analogy, Coding Decoding, Blood Relations, Directions (Direction Test), Syllogisms, Logical Sequence Of Words, Data Sufficiency, Seating Arrangements, Puzzle Solving (Puzzles), Calendar, Clock, Cubes & Dices, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Data Arrangement
  3. English Language: Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Sentence Correction (Error Correction), Sentence Completion (Fill in the blanks), Vocabulary, Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Active Passive Voice (Voice), Direct and Indirect Speech, Cloze Test (Cloze Passage), Tenses, Subject Verb Agreement (Verb Noun Agreement), Preposition, Articles, Conjunction, Adverb
  4. Written English Test: English Writing Ability
  5. Coding: Coding Questions by Yash Sir, C Programming by Yash Sir, Programming in C++, Java, Python for Placements by Yash Sir
  6. Communication Round: Communication Assessment
  7. DBMS (Technical Interview): 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, Big Data Systems, NoSQL, Data Warehousing & Mining
  8. SQL (Technical Interview): SQL
  9. Operating Systems (Technical Interview): 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
  10. Computer Networks (Technical Interview): 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, Mobile Technology, Cloud Computing and IoT, Cyber and Info Security
  11. OOPs (Technical Interview): Object Oriented Programming (OOPS)
  12. HR Interview: MR & HR Interview Preparation
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This video is a tutorial on Data Sufficiency, a common format in competitive exams like the GMAT or GRE. The instructor, Yash Jain Sir, begins by introducing the topic and the importance of practice. The core of the video is a detailed walkthrough of a specific Data Sufficiency problem. The question asks whether 3^x is less than 500, given that x is an integer. Two statements are provided: Statement 1 is the inequality 4^(x-1) < 4^x - 120, and Statement 2 is the equation x^2 = 36. The instructor systematically analyzes each statement. For Statement 1, he simplifies the inequality to 4^x > 160, which leads to x > 3. For Statement 2, he solves for x, finding x = 6 or x = -6. He then evaluates the sufficiency of each statement individually and together, concluding that Statement 1 alone is sufficient to answer the question, while Statement 2 is not. The video uses a digital whiteboard for all calculations and explanations.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with a title card for 'DATA SUFFICIENCY' and a 'Questions' slide emphasizing the importance of practice. The instructor, Yash Jain Sir, introduces the topic. The main problem is presented on a digital whiteboard: 'Que: If x is an integer, is 3^x less than 500?'. Two statements are listed: 'Statement 1: 4^(x-1) < 4^x - 120' and 'Statement 2: x^2 = 36'. The five multiple-choice options for the Data Sufficiency format are displayed below.

  2. 2:00 – 5:00 02:00-05:00

    The instructor begins analyzing the problem. He first focuses on the main question, writing '3^x < 500' on the board. He then evaluates Statement 1: '4^(x-1) < 4^x - 120'. He simplifies this by subtracting 4^(x-1) from both sides, resulting in '4^x - 4^(x-1) > 120'. He factors out 4^(x-1), leading to '4^(x-1) * (4 - 1) > 120', which simplifies to '4^(x-1) * 3 > 120'. Dividing by 3 gives '4^(x-1) > 40'. He then calculates 4^3 = 64, which is greater than 40, so x-1 > 3, meaning x > 4. He then evaluates Statement 2: 'x^2 = 36', which gives x = 6 or x = -6.

  3. 5:00 – 9:26 05:00-09:26

    The instructor now evaluates the sufficiency of the statements. For Statement 1, he concludes x > 4. He then checks if this is sufficient for the main question. He calculates 3^4 = 81, 3^5 = 243, and 3^6 = 729. Since 3^6 = 729 is greater than 500, he determines that x must be less than 6. Therefore, x can be 5, 4, 3, etc. For x=5, 3^5=243<500, which is 'Yes'. For x=6, 3^6=729>500, which is 'No'. Since the answer is not unique, he concludes Statement 1 is not sufficient. For Statement 2, x=6 or x=-6. For x=6, 3^6=729>500, so 'No'. For x=-6, 3^(-6) is a fraction less than 1, so 'Yes'. Since the answer is not unique, Statement 2 is not sufficient. He then considers both statements together, but since Statement 1 is not sufficient, the combination cannot be sufficient. He concludes that the answer is (e) Both statements put together are not sufficient.

The video provides a comprehensive, step-by-step analysis of a Data Sufficiency problem. It demonstrates the core methodology: first, understand the question and the information required. Then, evaluate each statement independently to determine if it provides a unique answer. The instructor correctly identifies that Statement 1 leads to a range of values for x (x > 4) that result in both 'Yes' and 'No' answers to the main question, making it insufficient. Similarly, Statement 2 yields two different values for x, leading to different answers, making it insufficient. The video effectively teaches the process of testing sufficiency by finding counterexamples, which is a key skill for this type of question.

Loading lesson…