Short Trick to find HCF of more than 2 numbers

Duration: 6 min

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AI Summary

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This educational video provides a comprehensive lesson on finding the Highest Common Factor (HCF) of multiple numbers using the 'by parts' method. The video begins with an introduction to the topic, defining HCF and presenting the core formula: HCF(a,b,c) = HCF(HCF(a,b),c). The instructor then demonstrates this method with a detailed example, calculating HCF(24, 40, 42, 44). The process involves breaking down the four numbers into pairs, first finding the HCF of the first two numbers (24 and 40), which is 8. This result is then used to find the HCF with the next number (42), yielding 2. Finally, the HCF of 2 and 44 is calculated, resulting in 2. The video uses a digital whiteboard for all calculations and includes a small inset of the instructor, Yash Jain, who explains the steps. The lesson concludes with a final answer and a 'Thanks for Watching' screen.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with a title card for 'LCM & HCF' and transitions to a classroom-style animation. The instructor, Yash Jain, introduces the topic of HCF, defining it as the Highest Common Factor. The on-screen text clearly states 'Highest Common Factor (HCF)' and the formula 'HCF (a,b,c) = HCF (HCF (a,b),c)' is displayed. The instructor explains that this formula is the basis for the 'by parts' method, which will be used to find the HCF of three or more numbers by solving them in pairs.

  2. 2:00 – 5:00 02:00-05:00

    The instructor begins a worked example, writing 'HCF (24, 40, 42, 44)' on the digital whiteboard. He applies the 'by parts' method, first calculating HCF(24, 40). Using the Euclidean algorithm, he divides 40 by 24, getting a remainder of 16, then divides 24 by 16, getting a remainder of 8, and finally divides 16 by 8, getting a remainder of 0. The last non-zero remainder, 8, is the HCF of 24 and 40. This result is then used to find HCF(8, 42), which is shown to be 2. The process continues with HCF(2, 44), which is 2. The instructor's voiceover explains each step of the calculation.

  3. 5:00 – 6:23 05:00-06:23

    The final calculation is completed, showing that HCF(2, 44) is 2. The instructor writes the final answer, 'HCF (24, 40, 42, 44) = 2', on the screen. The video then transitions to a black screen with an orange and white 'THANKS FOR WATCHING' message, concluding the lesson.

The video presents a clear, step-by-step demonstration of the 'by parts' method for calculating the HCF of multiple numbers. It effectively breaks down a complex problem into a series of simpler, manageable calculations. The use of a digital whiteboard allows for a clean and organized presentation of the mathematical process, while the instructor's narration provides a clear explanation of the underlying logic, making the concept accessible for students.