Simple interest is calculated by multiplying the principal (p), interest rate (r), and time (n). The document provides examples of calculating simple interest, principal, time, interest earned, and amount using the simple interest formula (I = p × n × r) for a principal of Rs. 6500 at an interest rate of 6% per annum over various time periods.

2. Simple Interest:
A quick method of calculating the interest charge on a
loan. Simple interest is determined by multiplying the
interest rate by the principal by the number of periods.
i.e I = p × n × r
where p is the loan amount
r is the interest rate
n is the duration of the loan
Example-1
Find the simple interest on Rs.6500 for 04 years at 6% per
annum.
Solution:
P = 6500
n = 4
r = 6% =
6
= 0.06
100
I = ?
We know that
I = P x n x r
I = 6500 x 4 x 0.06
I = Rs.1560

3. Example-2
Find the time in which Rs.6500 will earn Rs.1560 at 6%
per annum.
Solution:
P = 6500
r = 6% =
6
= 0.06
100
I = 1560
n = ?
We know that
I = P x n x r
n =
I 1560
=
p r 6500 0.06 
n = 4 years

4. Example-3
If Rs.6500 increases by Rs.1560 in 04 years, find the rate
of interest per annum.
Solution:
P = 6500
I = 1560
n = 4
r = ?
We know that
I = p x n x r
r =
I
p n
r =
1560

r = 0.06
r = 6%

5. Exampl-4
Find the principal which earns Rs.1560 in 4 years at 6%
per annum.
Solution:
r = 6% =
6
= 0.06
100
I = 1560
n = 4
P = ?
We know that
I = P x n x r
p =
I
n r
p =
1560

P = Rs.6500

6. Example-5
Find the amount of Rs.6500 in 04 years at 6% per annum.
Solution:
r = 6% =
6
= 0.06
100
P = 6500
n = 4
A = ?
We know that
A = P (1 + n r)
A = 6500{1+4(0.06)}
A = 6500(1.24)
A = Rs.8060

7. Example-6
In what time will Rs.6500 amount to Rs.8060 at 6% per
annum.
Solution:
A = Rs.8060
r = 6% =
6
= 0.06
100
P = Rs.6500
n = ?
We know that
I = A – P
I = 8060 – 6500
I = Rs.1560
Now
n =
I 1560
=
p r 6500 0.06 
n = 04 years