RD Sharma Class 7 Solutions Chapter 13 - Simple Interest (Ex 13.1) Exercise 13.1 - Free PDF
FAQs on RD Sharma Class 7 Solutions Chapter 13 - Simple Interest (Ex 13.1) Exercise 13.1
1. How can I use the RD Sharma Solutions for Class 7 Maths Chapter 13, Exercise 13.1, to master simple interest calculations?
Vedantu's RD Sharma Solutions for Exercise 13.1 provide detailed, step-by-step answers for all word problems. To master the topic, first attempt to solve a problem on your own. Then, compare your method with the one provided in our solutions. Pay close attention to how the Principal, Rate, and Time are identified from the word problem and correctly substituted into the formula. This helps in understanding the correct problem-solving approach as per the CBSE curriculum.
2. What is the correct step-by-step method to solve a typical simple interest word problem found in Exercise 13.1?
The correct method for solving simple interest problems involves a clear, structured approach as demonstrated in our solutions:
Step 1: Carefully read the problem to identify the given values: Principal (P), Rate of Interest (R), and Time (T).
Step 2: Write down the formula for Simple Interest: SI = (P × R × T) / 100.
Step 3: Substitute the identified values correctly into the formula.
Step 4: Perform the calculation to find the Simple Interest (SI).
Step 5: If the question asks for the total Amount (A), use the formula A = Principal + Simple Interest.
3. When solving problems in Exercise 13.1, why is it crucial to convert the time period into years?
It is crucial to convert the time period into years because the rate of interest (R) is almost always given as 'per annum' (p.a.), which means 'per year'. The simple interest formula is consistent only when both the Rate (R) and Time (T) are in the same unit, which is years. If you use time in months or days without converting, the calculated interest will be incorrect. For example, a period of 6 months must be written as 0.5 or 1/2 years in the formula.
4. How do I find the Principal (P) if the Simple Interest (SI), Rate (R), and Time (T) are given in a question from Ex 13.1?
To find the Principal (P) when the other values are known, you need to rearrange the basic Simple Interest formula. The standard formula is SI = (P × R × T) / 100. By manipulating this equation to solve for P, you get the formula: Principal (P) = (SI × 100) / (R × T). The RD Sharma solutions for Exercise 13.1 clearly demonstrate the application of this rearranged formula for relevant problems.
5. What is a common mistake students make when calculating the final Amount, and how do the solutions help avoid it?
A common mistake is providing the Simple Interest (SI) as the final answer when the question actually asks for the total Amount (A). The Amount is the sum of the initial Principal and the interest earned. Our RD Sharma solutions help avoid this by clearly separating the steps. They first calculate the SI and then explicitly show the final calculation for the Amount using the formula A = P + SI, which reinforces the correct procedure.
6. What key terms must I understand to solve the problems in RD Sharma Class 7 Chapter 13, Exercise 13.1?
To successfully solve the problems in this exercise, you must clearly understand these four key terms:
Principal (P): The initial sum of money that is borrowed or lent.
Rate of Interest (R): The percentage at which interest is calculated on the principal, usually per year (per annum).
Time (T): The duration for which the money is used, which must be expressed in years for calculations.
Simple Interest (SI): The calculated extra amount paid for using the principal for a specific time.
Our solutions for Exercise 13.1 show how to correctly identify and use these values in every problem.
