Refer the below formulas and previous year questions.

Interest is defined as money charged for borrowing the money from someone/banks. There are four words mainly used in this category. Those are

a) Principal: It’s denoted by ‘P’. Principal is the amount of money borrowed for a certain time.

b) Rate of interest: It’s denoted by ‘R’. Money paid for Rs. 100 per year called rate of interest.

c) Amount: It’s denoted by ‘A’. The sum of Principal and interest is called amount.

d) Time: Denoted by ‘T’. It’s the period for which we borrowed money is called Time.

Simple interest is denoted by ‘SI’. If the interest is calculated on the amount which we borrowed at any rate of interest for any period of time is called simple interest.

SI = (P * T * R) / 100

A = P + SI

P = (100 * A) / (100 + RT)

SI = ART / (100 + RT)

P = (100 * SI) / TR

T = (100 * SI) / PR

R = (100 * SI) / PT

SI = Simple Interest; A = Amount; P = Principal; T = Time; R = Rate of interest

Previous year solved Questions:

**1. Anusha deposits an amount of Rs. 65800 to obtain a simple interest at the rate of 14% per annum for 4yr. What total amount will Anusha get at the end of 4 yr?**

A) Rs. 102648

B) Rs. 115246

C) Rs. 125578

D) Rs. 110324

E) None of these

Ans: A

Solution: Given data P = 65,800/-, R = 14%, T = 4yr

Simple Interest = { 65800*14*4} / 100 = 36848

Therefore Amount = P + SI => 65800 + 36848 = 102648

**2. Nandini borrowed some money at the rate of 6% per annum for the first 3yr, at the rate of 9% per annum for the next 5yr and at the rate of 13% per annum for the period beyond 8yr. If she pays a total interest of Rs. 8160 at the end of 11yr. how much money did she borrow?**

A) Rs. 12000

B) Rs. 10000

C) Rs. 8000

D) Data is inadequate

E) None of these

Ans: C

Solution: Assume sum borrowed = P

As per given data, {[P*6*3] / 100 + [P*9*5] / 100 + [P*13*3] / 100} = 8160

=> {18P + 45P + 39P} / 100 = 8160

=> 102P/100 = 8160

=> Rs. 8000