1. Simple interest Time in Years

2. Recap Lokesh decides to keep some money in a bank for 1 year.
After 1 year , the bank provides him an additional amount which is called
interest of Rs 400.
He then decides to keep the money in the bank for 1 more year
and gets the same interest of Rs 400 for that 1 year.
This type of interest where you get same interest every year is called
simple interest.
In simple interest, the interest amount remains the same
because the interest is calculated based on the original principal amount. 

3. INTEREST When we borrow (or lend) money ,we pay (or
receive) some additional amount in addition
to the original amount.
The additional amount that we receive is
termed as Interest (I).

4. Simple Interest
Simple Interest- Interest is termed as Simple Interest because it is always calculated on the initial amount (ie) Principal.
Principal (P)- The amount borrowed / lent is called the Principal (P).
Rate(R)- Rate of interest is the amount calculated annually for Rs.100
Period of time(n) - mostly expressed in years.

5. Simple Interest
To find simple interest we use the following formula:
I =
Rate of interest
Interest
Principal
Number of years

6. Ans: Arun will earn Rs.90 interest in 4 years.
Example 1: Arun has Rs.750 in a savings account that pays 3%
simple interest. How much interest will he earn in 4 years?
Solution:
Given : p=750 , n=3 , r = 4 To Find:- simple interest
= 90
Ans: Arun will earn Rs.90 interest in 4 years.

7. Ans: Arun will earn Rs.6000 interest in 10 years.
Example 2: Arun has Rs in a savings account that pays 5%
simple interest. How much interest will he earn in 10 years?
Solution:
Given : p=12000 , n=10 , r = 5 To Find:- simple interest
= Rs 6000
Ans: Arun will earn Rs.6000 interest in 10 years.

8. Try these
Find simple interest when rate =5% per annum,principal=Rs 2500
and no of years is 5?