Short Trick for Questions on Difference in Amount

Duration: 12 min

This video lesson is available to enrolled students.

Inside: a video lesson and guided study material.

Module outline

Quantitative Ability: Percentage, Profit and Loss, Ratio and Proportion (Ratios), Average, Time and Work, Speed Time and Distance, Simple Interest and Compound Interest, Age Problems, Number System, Divisibility Rules, HCF LCM, Algebra, Permutation and Combination, Probability, Data Interpretation, Logarithm, Sequence and Series (Series), Powers and Exponents (Surds and Indices), Speed Mathematics and Basic Mathematics
Logical Reasoning: Seating Arrangements, Puzzle Solving (Puzzles), Data Arrangement, Coding Decoding, Blood Relations, Directions (Direction Test), Ranking, Order and Sequence, Data Sufficiency, Venn Diagram, Inequality, Series (Number and Letter Series) (Numerical Relations and Reasoning), Logical Sequence Of Words, Deductive and Inductive Reasoning (Logical Deduction and Induction) (Prepositional Reasoning), Selection Decision Table (Decision Making), Analogy, Non Verbal Reasoning (Spatial Aptitude) (Spatial Reasoning) (Visual Reasoning)
Verbal Ability: Comprehension / Reading Comprehension / Unseen Passages (Critical Reasoning) (Paragraph Questions), Subject Verb Agreement (Verb Noun Agreement), Tenses, Articles, Preposition, Conjunction, Modals, Active Passive Voice (Voice), Direct and Indirect Speech, Vocabulary, Sentence Re-arrangements (Para Jumbles) (Narrative Sequencing), Sentence Completion (Fill in the blanks), Sentence Correction (Error Correction), Cloze Test (Cloze Passage), Facts, Inference and Judgements
Programming Fundamentals (Technical): C Fundamentals
Data Structures (Technical): Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing
Algorithms (Technical): Algorithm Analysis, Sorting Algorithms, Greedy Algorithms, Dynamic Programming, Minimum Spanning Trees, Shortest Path Algos, Time Complexity Analysis, Advanced Algorithms
OOPs (Technical): Object Oriented Programming (OOPS)
DBMS (Technical): 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
SQL (Technical): SQL
Operating Systems (Technical): 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
Computer Networks (Technical): 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
Software Engineering (Technical): Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management
Coding/Automata Round: Coding Questions by Yash Sir, C Programming by Yash Sir, Programming in C++, Java, Python for Placements by Yash Sir, Pseudo Codes
Personality / Behavioral Assessment: Behavioral Assessment (Behavioral Competency Profiling) (Psychometric Test)
Writing Assessment: English Writing Ability

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

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.
2:00 – 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.
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%.
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.