Practice Questions
Duration: 11 min
This video lesson is available to enrolled students.
AI Summary
An AI-generated summary of this video lecture.
This educational video is a lecture on calculating profit in scenarios involving dishonest weight practices, a common topic in aptitude and placement exams. The instructor begins by presenting a problem where a shopkeeper sells onions at a 10% profit but uses a weight that is 20% less than the original. He then introduces a general formula for calculating total profit: (Profit% + Decrease% in weight) / (100 - Decrease% in weight) * 100. He applies this formula to solve the first problem, arriving at a total profit of 37.5%. The lecture continues with a second example, where a shopkeeper claims to sell per kg but uses 960 grams instead of 1 kg, and a third example with a fruit vendor using 900 grams for a kg. The instructor consistently uses the same formula to solve each problem, demonstrating its application. The video concludes with a final summary of the method and a thank you message.
Chapters
0:00 – 2:00 00:00-02:00
The video opens with a conceptual image of a 3D figure standing on a seesaw, with 'PROFIT' in green on one side and 'LOSS' in red on the other, symbolizing the balance of financial outcomes. The scene then transitions to a lecture format, where the instructor presents the first problem: 'A shopkeeper sells onion on a profit of 10%. The weight he uses is 20% less than original weight. What will be his total profit?'. The options are listed as a) 17.5%, b) 27.5%, c) 37.5%, d) 47.5%. The instructor introduces the problem, which is noted as an 'IMPORTANT QUESTION ASKED IN IBM EXAM (2018)'. The visual includes a humorous image of a woman crying while holding a small onion in a box, with a tweet overlay about onion prices, adding a comedic element to the serious topic.
2:00 – 5:00 02:00-05:00
The instructor begins to solve the first problem by writing the formula for total profit on a green chalkboard. The formula is clearly written as: Profit% = (Profit% + decrease% in weight) / (100 - decrease% in weight) * 100. He then substitutes the values from the problem: Profit% = 10 and Decrease% in weight = 20. The calculation is shown step-by-step: (10 + 20) / (100 - 20) * 100, which simplifies to 30 / 80 * 100. The instructor explains that this calculation results in 37.5%. He confirms that the correct answer is option (c) 37.5%. The visual shows the instructor's hand writing the formula and calculations in yellow chalk, with the problem statement and options visible at the top of the screen.
5:00 – 10:00 05:00-10:00
The instructor moves to a second problem: 'A shopkeeper claims to sell per kg NIRMA on the cost price but he uses a weight of 960 grams instead of 1 Kg. How much percentage of profit he earns by doing this?'. He applies the same formula, writing it on the board: Profit% = (Profit% + decrease% in weight) / (100 - decrease% in weight) * 100. He identifies the profit% as 0 (since he sells at cost price) and the decrease% in weight as (1000 - 960) / 1000 * 100 = 4%. The calculation becomes (0 + 4) / (100 - 4) * 100, which is 4 / 96 * 100. He simplifies this to 25 / 6, which equals 4 + 1/6%. He then presents a third problem: 'A dishonest fruit vendor sells his goods at Cost Price, but he uses 900 gm instead of 1 kg weight, his gain percent is'. He applies the formula again, with profit% = 0 and decrease% in weight = 10%. The calculation is (0 + 10) / (100 - 10) * 100 = 10 / 90 * 100 = 100 / 9 = 11 + 1/9%. The instructor emphasizes that this is a standard method for solving such problems.
10:00 – 10:35 10:00-10:35
The video concludes with a final summary of the method. The instructor reiterates the formula for calculating profit when a dishonest shopkeeper uses a lesser weight. The screen displays a blue, abstract background with the text 'THANKS FOR WATCHING' in large white letters. The instructor's voiceover thanks the viewers for watching and mentions that a quiz containing important previous year IT companies' questions will be discussed at the end of the video, encouraging viewers to watch until the end.
The video provides a clear and structured lesson on a specific type of profit and loss problem. It begins by introducing a real-world scenario involving a dishonest shopkeeper, which is a common theme in aptitude tests. The core of the lesson is the derivation and application of a single, powerful formula: Profit% = (Profit% + decrease% in weight) / (100 - decrease% in weight) * 100. The instructor demonstrates this formula with three distinct examples, each with different values, reinforcing the method's versatility. The progression from a simple problem to more complex ones, all solved using the same formula, effectively teaches a universal problem-solving technique. The use of a green chalkboard for calculations and clear, step-by-step writing makes the method easy to follow and replicate for students preparing for competitive exams.