Short Trick for Questions on Difference in Amount

Duration: 12 min

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Module outline

  1. About Course: About the Course
  2. General Aptitude & Reasoning: Number System, Percentage, Ratio and Proportion (Ratios), Average, Profit and Loss, Simple Interest and Compound Interest, Time and Work, Speed Time and Distance, Mixture and Alligation, Data Interpretation, Algebra, Probability, Permutation and Combination, Venn Diagram, HCF LCM, Divisibility Rules, Age Problems, Pipe and Cistern, Partnership, Linear Algebra, Sequence and Series (Series), Statistics, Powers and Exponents (Surds and Indices), Arithmetic, Mensuration and Geometry, Calculus, Trigonometry, Vectors, Speed Mathematics and Basic Mathematics, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning), Analogy, Series (Number and Letter Series) (Numerical Relations and Reasoning), Puzzle Solving (Puzzles), Syllogisms, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Calendar, Seating Arrangements, Coding Decoding, Blood Relations, Directions (Direction Test), Clock, Analytical Reasoning (Counting Figures Reasoning), Ranking, Order and Sequence, Logical Sequence Of Words, Inequality, Data Sufficiency, Cubes & Dices
  3. Computer Networks & Cybersecurity: 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
  4. Programming, Data Structures & Algorithms: C Fundamentals, Control Flow, Functions, Arrays & Pointers, Storage Classes, Structures & Enums, DMA, Macros, Scoping & File Handling, OOPS with C++, Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, Algorithm Analysis, Time Complexity Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Advanced Algorithms
  5. AI, Machine Learning, Big Data & Cloud: Emerging Tech Trends, Artificial Intelligence, Big Data Systems, Approaches to AI, Search Algorithms, Knowledge Representation, Cloud Computing
  6. Digital Logic & Computer Organization: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation, Basics of COA, Floating Point Rep, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Register Transfer and Microoperations, Control Unit Design, Programming the Basic Computer
  7. TOC & Compiler: 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, 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
  8. Discrete Mathematics: Set Theory, Relations, Functions, Graph Theory, Group Theory, Propositional and Predicate Logic
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  10. Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management, Object Oriented Technology, HTML Basics, JavaScript-Basics, Java, XML
  11. Database Management System: 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, Data Warehousing & Mining, Enhanced Data Models, NoSQL
  12. Other Recurring CS Topics: Basics of Computer Graphics, 2-D Geometrical Transforms and Viewing, Multimedia
  13. Live Classes: ISRO Live classes
  14. Full Mock Test:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This educational video is a lecture on simple and compound interest, presented by an instructor named Yash Jain. The video begins with an introductory slide that visually represents financial growth with a graph and coins, setting the context for the topic. The main content consists of two example problems. The first problem asks to find the rate of interest given that a sum of money amounts to Rs. 6200 in 4 years and Rs. 7100 in 7 years. The instructor solves this by first establishing the formula for the amount (A = P + SI) and then calculating the difference in the total amounts (A2 - A1) to find the interest earned over the 3-year period between the two time points. This leads to the calculation of the annual simple interest, which is then used to find the principal and finally the rate of interest. The second problem is similar, asking for the rate of interest when a sum amounts to Rs. 14880 after 3 years and Rs. 16800 after 5 years. The instructor applies the same method, calculating the interest for the 2-year period and then determining the annual interest and the rate. The video concludes with a 'Thank You' screen. The teaching style is direct, with the instructor writing out the formulas and calculations on a digital whiteboard, explaining each step clearly.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with a title slide for a lesson on 'Simple and Compound Interest'. The slide features a graphic of a rising graph and stacks of coins, symbolizing financial growth. The instructor, Yash Jain, appears in a small window on the right, introducing the topic. The text on the slide also indicates the lesson is from 'Knowledge Gate Educator' and covers the topic from 'Basic To Advance'. The instructor begins to explain the concept of simple interest, setting the stage for the problems to be solved.

  2. 2:00 – 5:00 02:00-05:00

    The first problem is presented on the screen: 'A sum of money amounted to Rs.6200 in 4 years and Rs.7100 in 7 years. Find the rate of interest.' The instructor begins the solution by writing the formula for the amount in simple interest: A = P + SI. He then writes the equations for the two scenarios: A1 = P + SI1 and A2 = P + SI2. He explains that the difference between the two amounts (A2 - A1) will give the interest earned over the 3-year period between the two time points, which is 7100 - 6200 = 900. This is a key step in the problem-solving process.

  3. 5:00 – 10:00 05:00-10:00

    The instructor continues solving the first problem. He uses the formula for simple interest, SI = (P * R * T) / 100, to express the interest for the 3-year period. He calculates that the interest for 3 years is 900, so the annual interest is 900 / 3 = 300. He then uses the amount after 4 years (6200) to find the principal: P = A - SI = 6200 - (300 * 4) = 6200 - 1200 = 5000. With the principal (P = 5000) and the annual interest (300), he calculates the rate of interest: R = (SI * 100) / (P * T) = (300 * 100) / (5000 * 1) = 6%. The final answer is R = 6%.

  4. 10:00 – 12:19 10:00-12:19

    The video transitions to a second problem: 'A sum of money amounted to Rs.14880 after 3 years and to Rs.16800 after 5 years. Find the rate of interest.' The instructor applies the same method. He calculates the interest for the 2-year period: 16800 - 14880 = 1920. The annual interest is 1920 / 2 = 960. He then finds the principal using the amount after 3 years: P = 14880 - (960 * 3) = 14880 - 2880 = 12000. Finally, he calculates the rate: R = (960 * 100) / (12000 * 1) = 8%. The video ends with a 'THANK YOU FOR WATCHING' screen.

The video provides a clear, step-by-step demonstration of how to solve simple interest problems where the principal is unknown. The core teaching method is to use the difference in the total amounts over a known time interval to find the annual interest. This annual interest is then used to back-calculate the principal and, finally, the rate of interest. The instructor consistently applies the formula A = P + SI and the formula for simple interest, SI = (P * R * T) / 100, to solve two distinct problems, reinforcing the method through repetition. The visual aid of writing on a digital whiteboard helps to follow the logical progression of the calculations.

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