Profit Loss on Selling Multiple Items

Duration: 7 min

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AI Summary

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The video is a tutorial on solving a profit and loss problem from a previous competitive exam. It begins by presenting a question about Vijay Malya selling 30 Kingfisher soda items at Rs. 1500, incurring a 25% loss, and then needing to find the new selling price 'x' to achieve a 20% profit. The instructor first demonstrates the 'Conventional Method' by calculating the cost price (CP) using the formula SP = CP(100-loss)/100, which results in CP = 200. He then calculates the new selling price for a 20% profit using SP = CP(100+profit)/100, which gives SP = 240. The final answer is the total selling price for 30 items, 240 * 30 = 7200. The video then introduces a faster 'Chain Rule' method, which directly calculates the new selling price as (100+profit)/(100-loss) * original SP, resulting in (120/75) * 1500 = 240, and then multiplies by 30 to get 7200. The video concludes with a 'Thanks for Watching' screen.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The video opens with a title card displaying a 3D animation of a person on a seesaw, with 'PROFIT' on the left and 'LOSS' on the right, symbolizing the balance between profit and loss. This transitions to a slide with a question: 'Q1: Vijay Malya encounters 25% loss on selling 30 Kingfisher soda at Rs. 1500. Now in order to gain 20% profit on same 30 items, he sells these items at some 'x' rupees. Find the value of 'x' ?'. The slide also includes a meme of three men on a motorcycle with the text 'JALDI AIRPORT BHAGA' and 'VIJAY MALLYA RETURN AA RAHA HAI..'. The instructor, Yash Jain Sir, is visible in a small window, introducing the problem and stating it's an important question from the 2018 TCS exam.

  2. 2:00 – 5:00 02:00-05:00

    The instructor begins the 'Conventional Method' of solving the problem. He writes on a virtual green board, starting with the formula for selling price with a loss: SP = CP(100-loss)/100. He substitutes the given values: 1500 = CP(100-25)/100, which simplifies to 1500 = CP(75)/100. He then solves for CP, writing CP = (1500 * 100) / 75, which he calculates as CP = 200. He then uses the formula for selling price with a profit: SP = CP(100+profit)/100. Substituting the values, he writes SP = 200(100+20)/100, which simplifies to SP = 200(120)/100, resulting in SP = 240. He notes that this is the selling price per item.

  3. 5:00 – 7:20 05:00-07:20

    The instructor introduces the 'Chain Rule (5 second Short Trick)'. He writes the formula: (100+profit)/(100-loss) * original SP. He substitutes the values: (100+20)/(100-25) * 1500, which is (120/75) * 1500. He simplifies 120/75 to 8/5, so the calculation becomes (8/5) * 1500 = 240. He confirms this is the new selling price per item. He then multiplies 240 by 30 to get the total selling price for all 30 items, which is 7200. The final answer is x = 7200. The video ends with a 'Thanks for Watching' screen.

The video provides a comprehensive solution to a profit and loss problem, demonstrating two distinct methods. The 'Conventional Method' is a step-by-step approach that first calculates the cost price from the initial loss and then uses it to find the new selling price for the desired profit. The 'Chain Rule' method is a shortcut that directly relates the new selling price to the old one using the ratio of the profit and loss percentages, allowing for a much faster calculation. The core concept is that the cost price remains constant, and the problem is solved by finding the new selling price that yields a 20% profit on that fixed cost.