Some Important Observations and Short Tricks

Duration: 22 min

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Module outline

  1. Paper 1 | Reasoning Test: Series (Number and Letter Series) (Numerical Relations and Reasoning), Coding Decoding, Data Sufficiency, Syllogisms, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Seating Arrangements, Blood Relations, Puzzle Solving (Puzzles), Venn Diagram, Analogy, Ranking, Order and Sequence, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Selection Decision Table (Decision Making), Logical Sequence Of Words, Cubes & Dices, Analytical Reasoning (Counting Figures Reasoning), Calendar, Alphabet and Word Tests, Numerical Reasoning, Number System, Averages, Mixtures and Alligation, Percentages, Series Completion, Analogy and Classification, Patterns in Two-Dimensional Figures, Coding and Decoding, Mathematical Operations, Direction Sense, Algebra, Logical Deduction and Induction, Syllogisms and Venn Diagrams, Critical Reasoning, Order, Ranking and Sequence, Reading Comprehension, Profit, Loss and Discount, Constraint Puzzles, Speed, Time and Distance, Traverse Surveying, Ratio and Proportion, Time and Work, Mensuration, Permutations and Combinations, Clocks and Calendars, Data Interpretation, Assembling and Grouping of Shapes, Transformation of Shapes, Three-Dimensional Patterns and Visualization, Cubes and Dice, Vocabulary, Blood Relations, Data Sufficiency
  2. Paper 1 | Numerical Analysis: Number System, HCF LCM, Percentage, Ratio and Proportion (Ratios), Average, Sequence and Series (Series), Powers and Exponents (Surds and Indices), Algebra, Statistics, Data Interpretation, Mental Ability, Arithmetic, Logarithm, Profit and Loss, Simple Interest and Compound Interest, Speed Time and Distance, Mixture and Alligation, Mensuration and Geometry, Permutation and Combination, Probability, Sequences and Series, Powers, Surds and Logarithms, Subject-Verb Agreement, Sentence Completion, Geometry, Sentence Structure and Correction, Data Sufficiency, Trigonometry, Measurement and Quantity Take-Off, Signal Space and Optimum Detection, Probability, Statistics, Algebra, Time and Work, Speed, Time and Distance, Data Interpretation, Graph Theory, Combinatorics
  3. Paper 1 | General Knowledge: State Wise GK, History, Geography, GK- Current Affairs, Static General Knowledge, Polity, Indian Economy
  4. Paper 1 | DBMS: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, File Organization & Indexing, Relational Algebra, SQL, Transaction Management, Concurrency Control, Relational Calculus, Database Security & Authorization, Database Recovery
  5. Paper 1 | Data Communication & Network: 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, Network Security, Security in Mobile and Wireless Computing, Input Output Organisation, File Management, Hardware Basics, Terms & Abbreviations, Protocols & Services, Network Access Technologies, Cyber Safety and Security, Basics of COA
  6. Paper 2 | System Analysis & Design: Fundamentals of Systems and Information Systems, SDLC and Development Approaches, Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Documentation and Software Requirements Specification (SRS), SDD and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management, Security, Risk Management & Maintenance, extras
  7. Paper 2 | Programming Language (Java): Java Fundamentals, OOPS with Java, Array, String, IO & References, Generic & Collections, Multithreading, Java, Miscellaneous, Control Flow, OOPS with C++, Stack, C Fundamentals, Arrays & Pointers, Object Oriented Technology, Control Flow & Looping, Introduction to Python
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This lecture teaches foundational shortcuts for solving number and letter series, emphasizing pattern recognition over brute-force calculation. The instructor introduces three core operation types—addition, multiplication, and mixed (A+m)—and applies them to sequences like 5, 15, 45, 135, 405 (×3 pattern) and large powers of two. Reference tables for squares (1–50), cubes (1–20), and primes (1–200) are used to quickly identify missing terms in sequences such as 961, 1024, 1089, __, 1225 (answer 1156 = 34²) and 6, 15, 35, __, 143 (consecutive prime products). A difference-based method using the formula (a × p) + m is demonstrated on 2, 6, 14, 30 (answer 62). The final section covers miscellaneous series with alternating patterns and Fibonacci-like sums, concluding with a pair-based rule yielding 4 + 1 = 5.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The lesson opens with a title slide 'NUMBER SERIES - LETTER SERIES' showing the alphabet and numbers, followed by a 'Back To Basics' card with wooden letter blocks. The instructor presents the first puzzle: 5, 15, 45, 135, 405, ____, and a second: 524288, 65536, 8192, 1024, 128, 16, ____. On-screen text also shows 'Find the Next Number in this series: 5, 7, 12, 19, 31, 50, ?' as a teaser. The teaching cue is to return to foundational pattern recognition before solving.

  2. 2:00 – 5:00 02:00-05:00

    The instructor writes 'addition', 'multiplication', and 'mix (A+m)' as candidate patterns for 5, 15, 45, 135, 405. Arrows above the sequence show differences +10, +30, +90, and a calculation '(5x2)+5' illustrates the mixed method. The instructor then crosses out 'add x', writes 'inc ↑↑', and labels arrows between terms with 'x3'. A vertical calculation 405 × 3 = 1215 confirms the answer. For the second sequence, 'Sub. X' is crossed out while 'div.' and 'div + sub.' are checked; 128/16 = 2³ is written, and the exponent rule a^m/a^n = a^(m-n) explains the power-of-two division pattern.

  3. 5:00 – 10:00 05:00-10:00

    A slide titled 'Some Important Points' displays a table 'Squares 1 to 50' (1²=1 through 50²=2500). The row '961 1024 1089 __ 1225' is solved by filling the blank in red as '1156', with arrows labeling 31², 32², 33², 34², 35² and red circles marking the matching entries. A second slide 'Cubes 1 to 20' (1³=1 through 20³=8000) shows '729 1000 1331 1728 2197' annotated with arrows for 9³ through 13³ and a circle around 1728. The final frame in this window shows the halving sequence '360 180 90 __ 22.5' with a red arrow and handwritten cue 'dec', indicating division by 2.

  4. 10:00 – 15:00 10:00-15:00

    The instructor demonstrates a difference-based shortcut on 2, 6, 14, 30, __. Differences below the sequence are 4, 8, 16. The general formula '(a x p) + m' is written with p=2 and m=2. Verification: (14 × 2) + 2 = 30 confirms the pattern; the next difference is (30 × 2) + 2 = 62, which is added to the last term. The window then transitions to a prime-number table (1–200) and the sequence '6 15 35 __ 143'. The instructor writes '2x3=6' and '3x5=15', circles the first four primes (2, 3, 5, 7), and highlights 31, 37, 41, 43, 47 in the table to show consecutive prime products.

  5. 15:00 – 20:00 15:00-20:00

    Continuing the prime-product sequence, the instructor applies 5×7=35 and 11×13=143 to confirm the pattern, so the missing term is 7×11=77. The lecture then shifts to 'Miscellaneous Series'. The first example '1 10 2 9 3 8 4 7' is analyzed as an alternating pattern with the on-screen cue 'even', pairing terms that sum to 11. A second example '2 4 6 10 16 26 42' is shown as Fibonacci-like, with on-screen text '2+4=6, 4+6=10, 6+10=16, 10+16=26' confirming each term is the sum of the two preceding terms.

  6. 20:00 – 21:51 20:00-21:51

    The final example is the pair-based series '96 15 71 8 37 10 41'. The instructor applies a rule to adjacent pairs, and the on-screen calculation '4+1=5' gives the final answer. This closes the miscellaneous section, reinforcing that series may combine alternating patterns, adjacent-term sums, or pair-based rules rather than a single uniform operation.

The lecture builds a systematic toolkit for number-series problems. First, it classifies operations into addition, multiplication, and mixed (A+m), using the ×3 sequence 5→1215 as a clean multiplication example and the power-of-two division sequence to introduce exponent rules. Second, it provides reference tables (squares 1–50, cubes 1–20, primes 1–200) so students can spot missing terms by matching values rather than computing from scratch—e.g., 1156=34² and the prime-product gap 7×11=77. Third, it teaches a difference-based formula (a × p) + m for sequences where first differences themselves follow a pattern, as in 2, 6, 14, 30 → 62. Finally, it covers miscellaneous series with alternating pairs (1+10=11), Fibonacci-like sums (2, 4, 6, 10, 16, 26, 42), and pair rules (96, 15, 71, 8, 37, 10, 41 → 5). The central idea is to test simple operations first, use reference tables for recognition, and only then move to mixed or multi-step rules.

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