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