Worksheet on Simple Interest is here. Check your capabilities in solving simple interest problems. Follow the questions on calculating the rate of interest, simple interest, and the amount which is useful for candidates to calculate various problems. You can get various types of questions involving all the concepts of simple interest. Solve Simple Interest Worksheet Questions and make your preparation perfect.
The formulae to use while solving simple interest problems are,
A (Amount) = Principal + Interest
SI (Simple Interest) = (Principal * Rate * Time) / 100
Do Read: What is Simple Interest?
Simple Interest Questions with Solutions
Question 1:
The sum of Rs.800 amounts to Rs. 920 in 3 years at Simple Interest. Suppose that the rate increases by 3%. It would amount to how much?
Solution:
As given in the question,
Principal amount (P) = Rs. 800
Amount (A) = Rs. 920
We know the formula of Simple Interest
A = P + SI
Substitute the above values in the equation,
920 = 800 + SI
SI = 920 – 800
SI = 120
Therefore, Simple Interest SI = 120
We also know that,
SI = P * R * T / 100
Substituting the values in the above equation,
120 = 800 * R * 3 / 100
R = 120 / 3 * 8
R = 5 %
Therefore, the rate of interest is 5% per annum
As given that the amount increases in 3 years
Hence, 5 + 3 = 8 which implies R = 8
Now, we have to find the simple interest amount after 3 years
SI = P * R * T / 100
SI = 800 * 8 * 3 / 100
SI = 192
Finally, we find the amount after 3 years
A = P + SI
A = 800 + 192
A = 992
Therefore, the final amount after 3 years = Rs. 992
Hence, the final solution is Rs. 992
Question 2:
Find the simple interest on Rs. 68000 at 16 \(\frac { 2 }{ 3 } \) per annum for 9 months?
Solution:
As given in the question,
Principal = Rs. 68000
Rate of Interest = 16 \(\frac { 2 }{ 3 } \) = \(\frac { 50 }{ 3 } \)
Time = 9 Months = \(\frac { 9 }{ 12 } \)= \(\frac { 9 }{ 12 } \) years
We also know that,
Simple Interest (SI) = P * R * T / 100
Substitute the above values in the equation
SI = 68000 * \(\frac { 50 }{ 3 } \) * \(\frac { 3 }{ 42 } \) / 100
SI = 170 * 50
SI = 8500
Therefore, the Simple Interest is 8500
Hence, the final solution is 8500
Question 3:
3500 principal amount is given at 7% per annum rate of interest. Find the amount of interest at the end of the 2 years which will be received?
Solution:
As given in the question,
Principal = 3500
Rate of Interest = 7% per annum
Time = 2 years
Simple Interest (SI) = P * R * T / 100
SI = 3500 * 7 * 2 / 100
SI = 70 * 7
SI = 490
Therefore, Simple Interest = 490
We also know that
Amount = Principal + Interest
A = 3500 + 490
A = 3990
The amount of interest which will be received at the end of 2 years = Rs. 3990
Hence, the final solution is 3990
Question 4:
Laila has 2400 in her account and the rate of interest is 5%. Find out the years that will take to earn the interest as Rs. 240?
Solution:
As given in the question,
Principal = 2400
Rate of Interest = 5%
Time =?
Simple Interest = 240
We know that,
Simple Interest (SI) = Principal * Rate * Time / 100
240 = 2400 * 5 * T / 100
T = 240/24 * 5
T = 10/5
T = 2 years
Therefore, it takes 2 years to earn the interest as Rs. 240
Hence, the final solution is 2 years
Question 5:
Find Simple Interest and amount on Rs. 150 for 4 years at 5% per annum?
Solution:
As given in the question,
Principal = 150
Time = 4 years
Rate of Interest = 5% per year
We know that,
I = P* T * R / 100
I = 150 * 4 * 5 / 100
I = Rs. 30
To find the amount, we use the formula
Amount = Principal + Interest
A = 150 + 30
A = 180
Therefore, the amount of Rs. 150 for 4 years at 5% per annum is 180 and Simple Interest is Rs. 30
Question 6:
Ravi borrowed Rs. 1500 from Rajesh for 3 years 3 months at the rate of interest at 12% per annum. Find the amount at which his debt will be clear?
Solution:
As given in the question,
Principal = 1500
Time = 3 years 3 months = 3 + (3/12) = 13/4 years
Rate of Interest = 12%
We know that,
I = P * T * R / 100
I = 1500 * \(\frac { 13 }{ 4 } \) * 12 / 100
I = 15 * 13 * 3
I = 585
Therefore, the Interest is Rs. 585
To find the amount, we use the formula
Amount = Principal + Interest
A = 1500 + 585
A = 2085
Therefore, the amount Rs. 2085 will clear his debt in 3 years 3 months
Hence, the final solution is Rs. 2085
Question 7:
The principal is Rs. 6400, SI = Rs. 1152 and Rate of Interest = 6% per annum. Then find the time?
Solution:
As given in the question,
Principal = Rs. 6400
Simple Interest = Rs. 1152
Rate of Interest = 6% per annum
We know that,
I = P * T * R /100
T = I * 100 / P * R
T = 1152 * 100 / 6400 * 6
T = 3 years
Therefore, 3 years is the total time when the principal is Rs. 6400, SI = Rs. 1152 and Rate of Interest = 6% per annum
Hence, the final solution is 3 years.
Question 8:
The principal amount of Rs. 10,500 is invested for 9 years in an account paying annual simple interest. If the total amount of the interest earned was $1890. Find the interest rate?
Solution:
As given in the. question,
Principal Amount = Rs. 10,500
Time = 9 years
Total Interest Earned = $1890
We know that,
Rate of Interest = Interest / Principal * Time
R = 1890 / 10,500 * 9
R = 1890 / 94,500
R = 0.2
R = 2%
Therefore, the interest rate = 2%
We also know that,
I = P * T * R
I = 10,500 * 0.2 * 2
I = 1890
Hence, If the total amount earned was $1890 then the interest rate = 1890
Question 9:
John won $26,000 at the casino. He wants to put the part in government bonds paying 3% simple interest and the remaining in paying real estate funds at 8% annual simple interest. His C.P.A tells him he needs to have a total annual income of $1680 from two investments. How much should he invest in each of them?
Solution:
Let x be the amount invested at 3%,
then 26000 – x = amount invested at 8%
1680 = .03 + 0.8 (26000 – x)
1680 = 0.3x + 2080 – 0.8x
1680 = -0.5x + 2080
-400 = -0.5x
x = 8000
1680 = 8000. 0.03 + 0.08. 18000 where 8000. 0.03 is the interest from govt bonds
0.08. 18000 is the interest from real estate
= 240 + 1440 = 1680
Therefore, he should invest Rs. 240 in government bonds and Rs. 1440 in real estate
Question 10:
Kimber wants to save money and thus he opens a savings account in the bank with 1% interest per year. If she has 5,500 in her account. How much interest money will he earn in one year?
Solution:
As given in the question,
Principal amount = 5500
Rate of interest = 0.1%
Time = 1 year
We know that,
Interest = Principal * Time * Rate
I = 5500 * 0.1 * 1
I = 55
Therefore, the amount of money he earns in one year = Rs. 55