RD Sharma Class 7 Maths Solutions Chapter 13 - Simple Interest

The RD Sharma Solutions for Class 7 Maths Chapter 13 are developed by experts who have a lot of experience in teaching the subject. These solutions are carefully designed in a step-by-step manner with the utmost care to make students understand the concepts easily and ace their exams.

Here let us look into a few of the important topics from the Simple interest chapter which are frequently asked in the exams.

• Definition of principal

• Definition and meaning of interest

• Formula to calculate the amount

• Definition and meaning of simple interest

• Formula to calculate simple interest

• Verbally related problems on simple interest

Definition of principal

The principal amount which is denoted by the letter (P) is actually the initial or original amount of the loan, or the initial amount invested.

Definition and Meaning of Interest

Interest is the amount paid for borrowing others’ money. 

When we borrow money, we have to pay interest. When we lend money to borrowers, we get paid interest. 

It is an additional amount of money that is paid by the borrower to a lender apart from the amount borrowed. 

Suppose you borrowed Rs. 10 from your friend and you pay him Rs. 12 after a week. Here the additional amount of Rs. 2 is the interest

Formula to Calculate the Amount

The formula to calculate the amount is the principal amount plus the simple interest i.e. 

Amount = Principal + Simple interest

Definition and Meaning of Simple Interest

Simple Interest or (S.I.) is the process of computing the amount of interest for a principal amount of money at any particular rate of interest. The whole notion of simple interest depends on the time worth of money.

For illustration, a contractor Ms. Alexis wants to start a company and so she requested a bank to grant her a loan. The bank allowed her a sum of Rs 50,000/- for 4 years. At the end of four years, Alexis will have to return the money to the bank. She cannot just pay back the 50,000/-. It costs to borrow/loan money. The bank charges an 8.5% interest. So, Ms. Alexis must pay interest at the agreed 8.5% per annum.

Formula to Calculate Simple Interest

The formula for calculating simple interest is

Simple Interest (SI)     =   \[ \frac{P\times R\times T}{100}\]

Here, 

P =principal amount,

R =rate of interest

T =time period of interest.

Summary points for Calculating Simple Interest

• Simple Interest is calculated based on the amount borrowed and the time period until the return.

• The initial amount borrowed from the lender for a given time is called the principal.

• The extra money owed is called simple interest.

• Interest is the extra money that the borrower gives for utilizing the lender’s money.

• The time for which the money is borrowed is called the time period.

• The whole amount of money paid back after the stipulated time is called the amount.

Verbally Related Problems on Simple Interest

Q. An invested amount retrieves an interest of Rs.5000 at the rate of 10% in one year. What was the principal amount?

Solution: Let the principal amount be P, SI be the simple interest, R be the rate of interest, and T the time period.

Therefore,

Simple Interest (SI)        =   \[ \frac{P\times R\times T}{100}\]  = \[\frac{5000\times 10\times 1}{100}\] = 500

The principal amount is Rs.500.

Q.Alexa took a vehicle loan of Rs. 50000 on 28 February 2020 at the rate of 8% p.a. and paid it back on 16th July 2020. Find the total amount paid by Alexa?

Solution:

Here,

P = Rs.50,000

R = 8 % p.a.

T = 139/365

Given,

Time = Feb + March + April + May + June + July

         = 1 + 31  + 30  + 31  + 30  + 16 

         = 139 days

Now,

Simple Interest (SI)     =   \[ \frac{P\times R\times T}{100}\]

Simple Interest (SI)     =   \[\frac{50000\times 8\times 139}{100\times 365}\]

= Rs.1523.30

Hence, the amount paid by Alexa = Rs (50,000 + 1523.30) = Rs.51,523.30

We have provided step-by-step solutions for all exercise questions given in the pdf of Class 7 RD Sharma Chapter 13 - Simple Interest. All the Exercise questions with solutions in Chapter 13 - Simple Interest are given below:

Exercise 13.1

Exams Preparation Tips Using RD Sharma Class 7 Simple Interest

Students can improve their reasoning and analytical skills by solving various types of questions. RS Aggarwal Solutions provides all answers to the questions in this chapter, as well as improves the speed at which questions are answered. These tips often help the student in effectively preparing for the final exams and will come in handy for students while attempting any questions from the Simple Interest chapter.

• Recall the concepts of ratios and percentages before attempting the questions from SImple interest.

• Understand the concepts of Interest, profit and loss, and discounts clearly and then start with the Simple Interest concept.

• Remember the basic formulas of simple interest to solve the questions in quick time.

Conclusion

The expense of using or borrowing money without compound interest or interest on interest is known as simple interest. It's pretty simple to calculate because all you need is the principal sum borrowed and the time period. When you're a creditor, simple interest works in your favor because it holds the total sum you pay lower than it would be with compound interest. When you're an investor, though, it can work against you because you want your returns to compound as much as possible to get the most out of your investment. The RD Sharma Class 7 Simple Interest prepared by Vedantu experts will be really helpful for students when preparing for their board exams. The RD Sharma solutions also have a lot of practice questions for students to prepare for their exams with more confidence. The solutions are designed in such a way that students will get a unique and fun way of learning when referring to the RD Sharma Solutions for Class 7 Maths Chapter 13.