Short Trick to find LCM of decimal numbers
Duration: 7 min
This video lesson is available to enrolled students.
Inside: a video lesson and guided study material.
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- Paper-1 & 2 | Basic Numeracy / आधारभूत संख्यात्मक योग्यता: Ratio and Proportion / अनुपात और समानुपात, Divisibility Rules / विभाज्यता के नियम, Mixture and Alligation / मिश्रण और एलिगेशन, Permutation and Combination / क्रमचय और संचय, Logarithm / लघुगणक, Number System / संख्या पद्धति, HCF and LCM / महत्तम समापवर्तक और लघुत्तम समापवर्त्य, Sequences, Series and Combinatorics / अनुक्रम, श्रेणी और संयोजन, Time, Speed and Distance / समय, चाल और दूरी, Percentage / प्रतिशत, Average / औसत, Solid Mensuration / घन क्षेत्रमिति, Age Problems / आयु संबंधी प्रश्न, Arithmetic / अंकगणित, Statistics / सांख्यिकी, Probability / प्रायिकता, Profit, Loss and Discount / लाभ, हानि और बट्टा, Simple and Compound Interest / साधारण और चक्रवृद्धि ब्याज, Partnership / साझेदारी, Speed Mathematics and Basic Mathematics / द्रुत गणित और आधारभूत गणित, Algebra / बीजगणित, Simplification, Indices and Surds / सरलीकरण, घातांक और करणी, Time and Work / समय और कार्य, Pipe and Cistern / नल और टंकी, RSSB Specific Videos - Basic Numeracy / RSSB विशेष वीडियो - आधारभूत संख्यात्मक योग्यता, Sets, Relations, Functions and Discrete Mathematics / समुच्चय, संबंध, फलन और विविक्त गणित, Number Systems and Number Theory / संख्या पद्धति और संख्या सिद्धांत, Coordinate Geometry, Vectors and 3D Geometry / निर्देशांक ज्यामिति, सदिश और त्रिविमीय ज्यामिति, Polynomials, Equations and Complex Numbers / बहुपद, समीकरण और सम्मिश्र संख्याएँ
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- Paper-1 & 2 | Logical Reasoning and Analytical Ability / तार्किक तर्कणा एवं विश्लेषणात्मक क्षमता: Series / श्रेणी, Coding-Decoding / कूट लेखन एवं कूट वाचन, Data Sufficiency / आँकड़ों की पर्याप्तता, Non-Verbal Reasoning / अशाब्दिक तर्क, Syllogisms / न्यायवाक्य, Seating Arrangement and Puzzles / बैठक व्यवस्था एवं पहेलियाँ, Blood Relations / रक्त संबंध, Direction and Distance / दिशा एवं दूरी, Analytical Reasoning (Counting Figures Reasoning) / विश्लेषणात्मक तर्क (आकृति गणना तर्क), Mathematical Operations and Missing Numbers / गणितीय संक्रियाएँ एवं लुप्त संख्या, Calendar and Clock / कैलेंडर एवं घड़ी, Clock / घड़ी, Cubes, Dice and Figure Counting / घन, पासा एवं आकृतियों की गिनती, Venn Diagrams, Syllogism and Inequalities / वेन आरेख, न्याय वाक्य एवं असमानता, Analogy and Classification / सादृश्यता एवं वर्गीकरण, Order and Ranking / क्रम एवं रैंकिंग, Statement-Based Reasoning / कथन आधारित तार्किक विवेचन, Data Arrangement / आँकड़ों की व्यवस्था, Alphabet and Number Test / वर्णमाला एवं संख्या परीक्षण, Crypt Arithmetic / कूट अंकगणित
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- Paper 2 | Pedagogy / शिक्षाशास्त्र: Growth and Development / वृद्धि और विकास, Theories of Development / विकास के सिद्धांत, Concept of Pedagogy / शिक्षाशास्त्र की संकल्पना, Inclusive Education / समावेशी शिक्षा, Experiential Pedagogy / अनुभवात्मक शिक्षाशास्त्र, Assessment and Evaluation / आकलन और मूल्यांकन, Cognitive Processes / संज्ञानात्मक प्रक्रियाएँ, Socialisation and Gender / समाजीकरण और जेंडर, National Education Policy (NEP) 2020 / राष्ट्रीय शिक्षा नीति (NEP) 2020
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AI summary & chapters
AI Summary
An AI-generated summary of this video lecture.
This educational video, presented by Yash Jain from Knowledge Gate Eduventures, provides a comprehensive tutorial on calculating the Least Common Multiple (LCM) of decimal numbers. The lesson begins with an introduction to the topic, followed by a detailed explanation of the method. The core technique involves converting decimal numbers into whole numbers by multiplying them by a power of 10 (e.g., 10, 100) to eliminate the decimal point. The LCM of these resulting whole numbers is then calculated using prime factorization. Finally, the result is divided by the same power of 10 used in the initial conversion to obtain the LCM of the original decimals. The video demonstrates this process with two examples: first, LCM(2.8, 0.63), and second, LCM(0.18, 0.24, 0.3). The instructor uses a digital whiteboard to write out the steps, including the prime factorization of the numbers and the final calculation, ensuring a clear and logical progression of the concept.
Chapters
0:00 – 2:00 00:00-02:00
The video opens with a title card displaying 'LCM & HCF' against a digital, data-stream background. It then transitions to a classroom-style presentation with a cartoon teacher and a live video feed of the instructor, Yash Jain. The main topic is introduced on a green chalkboard: 'Least Common Common Multiple (LCM)'. The instructor begins the lesson by explaining the concept of LCM for decimals, setting the stage for the method to be demonstrated.
2:00 – 5:00 02:00-05:00
The instructor begins the first example, LCM(2.8, 0.63). He explains the method of converting decimals to whole numbers by multiplying by 100, as both numbers have two decimal places. The on-screen text shows the conversion: (2.8, 0.63) x 100 = (280, 63). He then proceeds to find the LCM of 280 and 63 using prime factorization. The board shows the factorization: 63 = 7 x 9 = 7 x 3 x 3, and 280 = 7 x 4 x 10 = 7 x 2 x 2 x 2 x 5. The LCM is calculated as 7 x 2 x 2 x 2 x 3 x 3 x 5 = 2520. The final step is to divide this result by 100, yielding 25.20 as the LCM of the original decimals.
5:00 – 7:23 05:00-07:23
The video presents a second example: LCM(0.18, 0.24, 0.3). The instructor explains that the highest number of decimal places is two, so the numbers are multiplied by 100. The conversion is shown as (0.18, 0.24, 0.3) x 100 = (18, 24, 30). He then finds the LCM of 18, 24, and 30. The prime factorization is shown: 18 = 2 x 3 x 3, 24 = 2 x 2 x 2 x 3, and 30 = 2 x 3 x 5. The LCM is calculated as 2 x 2 x 2 x 3 x 3 x 5 = 360. The final answer is obtained by dividing 360 by 100, resulting in 3.60. The video concludes with a 'THANKS FOR WATCHING' screen.
The video provides a clear, step-by-step guide to finding the LCM of decimal numbers, a topic that is often challenging for students. The instructor effectively breaks down the process into manageable steps: converting decimals to whole numbers, calculating the LCM of the whole numbers using prime factorization, and then converting the result back to a decimal. The use of two distinct examples reinforces the method and ensures the concept is well-understood. The visual aids, including the digital whiteboard and the instructor's clear explanations, make the lesson accessible and effective for learners preparing for competitive exams.

