Percentage IBPS PYQs

AI Summary

An AI-generated summary of this video lecture.

This educational video provides a comprehensive tutorial on solving percentage-based word problems commonly found in IBPS competitive exams. The instructor employs a systematic algebraic approach, consistently setting the total monthly income or salary as '100n' to simplify calculations involving sequential deductions and ratios. The lecture progresses through multiple complex scenarios, starting with basic salary distribution involving Provident Fund (PF) deposits and savings. Key concepts include calculating remaining balances after percentage deductions, applying ratios to the residual amounts for specific expenditures like medicine and groceries, and equating calculated portions to given monetary values to solve for the base variable 'n'. The teaching methodology emphasizes breaking down problems into sequential steps: determining the remaining income after each expense, converting fractions and percentages into numerical coefficients relative to 'n', and forming algebraic equations based on differences between expenses or final savings. The video demonstrates practical applications of these techniques through worked examples involving rent, travel, food, and family support allocations. Visual cues such as red circles around key values like '₹2,700' and handwritten equations on a digital whiteboard guide the viewer through the logical flow of each solution. The instructor also highlights common pitfalls, such as incorrectly applying percentages to the original total instead of the remaining balance. The final segment consolidates these methods by solving a multi-step problem where sequential deductions lead to a specific savings amount, reinforcing the utility of the '100n' method for handling complex percentage chains.

Chapters

1. 0:00 – 2:00 00:00-02:00

   The video opens with a quantitative aptitude question displayed in both English and Hindi regarding salary, PF deposits, and expenditures. The instructor underlines key phrases like "ratio 3:4" and the value "₹2,700" to emphasize critical data points. A red handwritten number "2700" appears on the screen and is circled, drawing attention to the specific expenditure amount. The instructor begins by writing "360" inside a red circle, indicating a calculated unit value. He then draws an arrow to "100%" and writes the equation "1% = 360/100" to solve for percentages. Finally, the text "100%" is written with an arrow pointing right, likely representing the total salary base. This initial segment establishes the foundational technique of using unit values to solve percentage problems.

2. 2:00 – 5:00 02:00-05:00

   The instructor transitions to a more complex problem involving salary, PF deposits, and savings. Red handwritten calculations appear below the question text. The instructor calculates the remaining salary after a 10% deduction as "90x" and then determines savings as "27%" of that amount. The remaining balance is circled as "63x" after subtracting the savings from the post-PF salary. New notes appear showing a ratio breakdown for expenditure, specifically writing "M/G = 3/4" to represent the medicine and grocery ratio. The instructor sets up an equation where the medicine expenditure equals 2700 to solve for the variable 'n' representing the salary base. The screen displays text such as "90n - (30/100 * 90) = 27% Save" and "90n - 27n = 63n", demonstrating the step-by-step reduction of the salary base.

3. 5:00 – 10:00 05:00-10:00

   The lecture moves to a word problem regarding monthly income allocation where Ram spends 20% of his monthly income on rent. The instructor sets the total monthly income as '100n' and calculates the remaining amount after deducting 20% for rent, resulting in '80n'. He then proceeds to calculate specific expenditures like travel and the amount given to his mother based on fractions of the remaining income. The screen shows "30% of 80n = 24n" and "2/5 x 80n = 32n", illustrating how to handle percentages and fractions applied to the remaining balance rather than the total. The problem states that the difference between his travel expenditure and the amount given to his mother is ₹11,200. The instructor uses these values to form an equation and solve for 'n', reinforcing the method of tracking remaining balances through sequential deductions.

4. 10:00 – 15:00 10:00-15:00

   The instructor solves another percentage-based word problem involving sequential deductions from an income. He sets the total monthly income as 100n and calculates remaining amounts after spending on rent, food, and travel. The screen displays "A spends 20% of his monthly salary on house rent" and "25% of the remaining salary on travelling", leading to a calculation where 80n x 25/100 = 20n, leaving 60n. The instructor then distributes the remainder in a 3:5 ratio for food and education, writing "F/C = 3/5 => F = 3/8, C = 5/8". The problem specifies that the difference between children's education and house rent is ₹700. By equating these calculated portions to the given difference, the instructor solves for n to find the total salary. This segment emphasizes the importance of applying ratios only to the final remaining amount after all percentage deductions.

5. 15:00 – 17:21 15:00-17:21

   The final segment consolidates the taught methods by solving a percentage-based word problem involving sequential deductions from an income. The instructor sets the total monthly income as 100n and calculates remaining amounts after spending on rent, food, and travel. The screen shows "Q. A spends 25% of his monthly income on rent..." followed by calculations: "75n - 15n = 60n", then "Rest Income = 60n x 40/100 = 24n", and finally "Rest Income = 60n - 24n = 36n". The final calculation equates the remaining savings (36n) to ₹10,800 to find the value of n. The instructor solves "n = 10800/36 = 30000", demonstrating the complete application of the sequential deduction method. This conclusion reinforces the utility of the '100n' approach for handling complex percentage chains and ensures students can independently solve similar problems.

The video effectively teaches a robust method for solving percentage word problems by standardizing the total amount as '100n'. This approach simplifies complex calculations involving sequential deductions and ratios. The instructor consistently demonstrates how to track the remaining balance after each expense, ensuring that subsequent percentages are applied correctly to the residual amount rather than the original total. Key techniques include converting fractions and percentages into numerical coefficients relative to 'n', setting up algebraic equations based on differences between expenses, and solving for the base variable to find the total income. The use of visual aids like red circles, underlined text, and handwritten equations on a digital whiteboard enhances clarity. The progression from simple salary deductions to multi-step problems involving ratios and differences builds student confidence in handling competitive exam questions. The consistent application of the '100n' method across diverse scenarios highlights its versatility and reliability for IBPS quantitative aptitude sections.