Short Tricks to Solve Questions Quickly
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 tutorial on calculating selling price given cost price and profit or loss percentage, presented by an instructor from Knowledge Gate. The video begins with a problem involving a packet of Vimal Pan Masala, where the cost price is Rs. 560 and the profit is 12.5%, and the instructor demonstrates three distinct methods to find the selling price. The first method uses the formula SP = CP(100 + P)/100. The second method, the Percentage Method, calculates the profit amount as a percentage of the cost price and adds it to the CP. The third method, the Ratio Method, converts the profit percentage into a ratio of profit to cost price, then uses the total parts to find the selling price. The video then transitions to a second problem about a cycle bought for Rs. 1400 and sold at a 15% loss, applying the same three methods to find the selling price. The instructor uses a green chalkboard to write out the formulas and calculations, and the video concludes with a 'Thanks for Watching' screen.
Chapters
0:00 – 2:00 00:00-02:00
The video opens with a title card showing a 3D figure on a balance scale with 'PROFIT' and 'LOSS' on either side, setting the theme of the lesson. The main content begins with a problem displayed on a green screen: 'Q1: The cost price of a packet of Vimal Pan Masala is Rs. 560 and sold at a profit of 12.5 %. Find the selling price?'. The instructor, visible in a small window, introduces the problem. The screen also shows a meme with Deepika Padukone and a man, and text indicating the question was asked in the TCS EXAM (2012). The instructor states that the video will cover three methods to solve such problems.
2:00 – 5:00 02:00-05:00
The instructor begins the first method, labeled 'Method 1 (Formula)'. He writes the formula SP = CP(100 + P)/100 on the green board. He substitutes the given values: CP = 560 and P = 12.5. The calculation proceeds as SP = 560(100 + 12.5)/100, which simplifies to SP = 560(112.5)/100. He then performs the multiplication and division, showing that 560 * 112.5 = 63000, and 63000 / 100 = 630. The final answer is SP = Rs. 630. The instructor explains that this is the most direct formula-based approach.
5:00 – 10:00 05:00-10:00
The instructor introduces the second method, 'Method 2 (Percentage Method)'. He explains that the profit is 12.5% of the cost price. He writes the formula SP = CP + P, where P = (12.5/100) * CP. He calculates the profit amount: (12.5/100) * 560 = 70. He then adds this profit to the cost price: SP = 560 + 70 = 630. The result is the same as the first method. He then moves to the third method, 'Method 3 (Ratio Method)'. He converts the profit percentage 12.5% into a fraction: 12.5/100 = 1/8. This means the profit is 1 part and the cost price is 8 parts. The selling price is the sum of these parts, so SP = 1 + 8 = 9 parts. He sets up a proportion: 8 parts = 560, so 1 part = 70. Therefore, 9 parts = 9 * 70 = 630. All three methods yield the same selling price of Rs. 630.
10:00 – 11:25 10:00-11:25
The video transitions to a new problem, Q2: 'A man buys a cycle of Rs. 1400 and sells it at a loss of 15 %. What is the selling price of the cycle?'. The instructor applies the same three methods. For Method 1, he uses the formula SP = CP(100 - L)/100, where L is the loss percentage. Substituting the values, SP = 1400(100 - 15)/100 = 1400(85)/100 = 1190. For Method 2, he calculates the loss amount as 15% of 1400, which is 210, and subtracts it from the CP: SP = 1400 - 210 = 1190. For Method 3, he converts 15% to a fraction, 15/100 = 3/20. This means the loss is 3 parts and the cost price is 20 parts. The selling price is 20 - 3 = 17 parts. He sets up the proportion: 20 parts = 1400, so 1 part = 70. Therefore, 17 parts = 17 * 70 = 1190. The video ends with a 'THANKS FOR WATCHING' screen.
The video provides a comprehensive, multi-method approach to solving profit and loss problems. It systematically demonstrates three distinct techniques—Formula, Percentage, and Ratio—on two different problems, one with a profit and one with a loss. The core concept is that the selling price can be found by either adding the profit to the cost price or subtracting the loss from it. The video emphasizes that while the methods differ in their approach, they all lead to the same correct answer, reinforcing the underlying mathematical principles. This structured presentation helps students understand the flexibility of problem-solving and choose the method that is most intuitive for them.