Top140 Simple Interest Questions For 100% Free [Effective]

Welcome to this guide on simple interest questions. For many, the topic of interest can be confusing, especially when diving into the world of finance. If you’ve ever wondered about simple interest questions or how to work with simple interest problems, you’re in the right place.

We frequently come across the word “interest” in our daily lives, especially when talking about money. There are different types of interests, with simple interest and compound interest being the most common. Through this article, we’ll be focusing extensively on simple interest questions and simple interest problems.

For those who prefer understanding in their native language, we’ve got simple interest questions in Hindi and the simple interest formula in Hindi. Our goal is to make simple interest in Hindi understandable for everyone.

But, what exactly is the simple interest formula? It’s a method used to figure out how much interest you’ll earn or owe over a period of time. The formula is straightforward: SI = PTR/100, where P is the Principal amount, T is the Time (in years), and R is the Interest rate.

Moreover, it’s essential to know that simple interest questions and simple interest and compound interest questions often appear in competitive exams. Whether it’s SSC, SBI, Railways, or any other state exams, mastering simple interest and compound interest questions can give you an edge. If you have a clear concept of ratio and percentage, you’ll find that tackling simple interest questions becomes much more manageable.

So, let’s dive deeper into simple interest questions and help you master the topic, whether in English or simple interest in Hindi. Happy learning!

Top140 Simple Interest Questions

81.(CI – SI)2 year = Rs. 450; R = 15%

Find Principal?

(CI – SI)2 वर्ष = 450 रूपए; R = 15%

मूलधन ज्ञात कीजिये?


Option”C” is correct

450 = P (15/100)(15/100)

∴ Principal = 20000 

82. If a sum of money on compound interest becomes three times in 4 years, then at the same interest rate, the sum will become 27 times in:

यदि कोई धनराशी 4 वर्षों में चक्रवृद्धि ब्याज पर तीन गुनी हो जाती है, तब समान ब्याज दर पर, यह धनराशी 27 गुना होगी:


Option”B” is correct

As per given question,

Formula: Amount = Principal (1 + Rate/100)Time

P(1 + r/100)4 = 3P

⇒ (1 + r/100)4 = 3

P(1 + r/100)n = 27P

⇒ (1 + r/100)n = 27

⇒ (1 + r/100)n = 33

⇒ (1 + r/100)n = [(1 + r/100)4]3

∴ n = 4 × 3 = 12

83. A certain sum invested on compound interest grows to Rs. 8,000 and Rs. 27,000 in three and six years, respectively when the interest is compounded annually, what is the percentage rate of interest?

एक निश्चित राशि को चक्रवृद्धि ब्याज पर निवेश करने पर वह राशि क्रमशः तीन वर्षों में 8,000 रूपए और छह वर्षों में 27,000 हो जाती है, जब ब्याज वार्षिक रूप से संयोजित किया जाता है, ब्याज की प्रतिशत दर क्या होगी?


Option”C” is correct

A = P(1 + r/100)n

Where, A = Amount

P = Principal

r = Rate of interest

n = Time period

When the sum amounts to Rs.8000 in 3 years:

8000 = P(1 + r/100)3       —-(1)

When the sum amounts to Rs.27000 in 6 years:

27000 = P(1 + r/100)6       —-(2)

Dividing equation (2) by equation (1)

27/8 = (1 + r/100)3

Taking cube root on both the sides

3/2 = 1 + r/100

⇒ 3/2 – 1 = r/100

⇒ 1/2 = r/100

⇒ r = 50%

∴ Rate of interest is 50% 

84. A sum of Rs. 18,000 is lent at 10% p.a compound interest, compounded annually, what is the difference between the compound interest for 3rd year and 4th year?

18,000 रुपये की राशि को 10% प्रति वर्ष चक्रवृद्धि ब्याज पर दिया जाता है, जो कि वार्षिक रूप से संयोजित है, तीसरे वर्ष और चौथे वर्ष के लिए चक्रवृद्धि ब्याज में क्या अंतर है?


Option”A” is correct

P = 18,000, r = 10% and t = 2 years, then

A = P (1 + r/100)2

A = 18,000 (1 + 10/100)2 = 18,000 × (11/10) × (11/10) = 21,780

So, Compound interest for 3rd year = 21780 × (10/100) = 2178

Amount will be after 3 year = 21780 + 2178 = 23958

So, compound interest for 4th year = 22958 × (10/100) = 2395.8

So, Difference of compound interest for 3rd year and 4th year = 2395.8 – 2178 = 217.80

Short Trick:

Compound interest rate for 1st year = 10%

Compound interest rate for 2nd year = 10% × (110/100) = 11%

Compound interest rate for 3rd year = 11% × (110/100) = 12.1%

Compound interest rate for 4th year = 12.1% × (110/100) = 13.31%

Difference of rates of compound interest for 4th and 3rd year = 13.31% – 12.1% = 1.21%

So, required difference = 18,000 × (1.21/100) = 217.80

85. A sum of Rs. 1200 is invested at compound interest (compounded half yearly). If the rate of interest is 10% per annum, then what will be the amount after 18 months?

1200 रुपए की एक राशि का निवेश चक्रवृद्धि ब्याज (अर्ध वार्षिक रूप से संयोजित होने पर) पर किया जाता है। यदि ब्याज की दर प्रति वर्ष 10% है, तो 18 महीने बाद राशि क्या होगी?


Option”D” is correct

Given, principle is Rs. 1200, rate is compounded half yearly so R = 5%, and time = 18 months

Since, Amount = P (1 + R/100)n

⇒ Amount = 1200 (1 + 5/100)3

⇒ Amount = 1200 × 9261/8000

∴ Amount after 18 months will be Rs. 1389.15

86. If after two years a sum becomes Rs. 4000 and after four years it becomes Rs. 6000 at the same rate of compound interest (compounded annually), then what is the sum?

यदि कोई राशि दो वर्ष के बाद 4000 रु. हो जाती है और उसी चक्रवृद्धि ब्याज (वार्षिक रूप से समायोजित) की दर से चार वर्ष के बाद 6000 रु. हो जाती है, तो वह राशि क्या है?


Option”B” is correct

According to the question

⇒ 4000 = P(1 + r/100)2      —- (1)

⇒ 6000 = P (1 + r/100)4     —- (2)

From (2) /(1),

⇒ 3/2 = (1 + r/100)2

From (1)

⇒ 4000 = P × 3/2

⇒ P = 8000/3 = Rs. 2666.66

∴ The sum is Rs. 2666.66

87.A sum of Rs. 2000 is invested at compound interest (compounding annually). If the rate of interest is 10% per annum, then what will be the amount after 30 months?

यदि 2000 रूपयों को चक्रवृद्धि ब्याज ( वार्षिक संयोजित किया जाता है)  पर निवेश किया जाता है। और यदि ब्याज की दर प्रति वर्ष 10% है, तब 30 महीने के बाद वह राशि कितनी हो जाएगी? 


Option”C” is correct

Interest for first year = 2000 × 10% = 200

⇒ Interest for second year = (2000 + 200) × 10% = 220

⇒ Interest for third year = (2000 + 200 + 220) × 10% = 242

⇒ But interest for 6 months in third year = Interest for third year/2 = 242/2 = 121

⇒ Total interest in 30 months = Interest for first year + Interest for second year + interest for 6 months in third year

⇒ Total interest in 30 months = 200 + 220 + 121 = Rs. 541

⇒ The amount after 30 months = 2000 + 541 = Rs. 2541

∴ The amount will be Rs. 2541 after 30 months.

88.Find the sum of money invested by a man in a scheme which offers Compound Interest at 8% rate of interest per annum if Compound Interest for 2 years is Rs. 6656

किसी योजना में 8% प्रति वर्ष की दर से चक्रवृद्धि ब्याज मिलता है यदि 2 वर्षों में चक्रवृद्धि ब्याज 6656 रुपए है, तो व्यक्ति द्वारा योजना में निवेश की गई धनराशि ज्ञात कीजिए।


Option”D” is correct

Compound interest = 8% + 8% + (8×8)/100 = 16.64%

⇒ 16.64% = 6656

⇒ 100% = 6656/16.64% = Rs. 40,000

89. A man borrowed some money and agreed to pay-off by paying Rs 3150 at the end of the 1st year and Rs 4410 at the end of the 2nd year. If the rate of compound interest is 5% per annum, then the sum is

एक आदमी ने कुछ राशि उधार ली और 1 वर्ष के अंत में 3150 रु. और दूसरे वर्ष के अंत में 4410 रु. का भुगतान करने पर सहमत हो गया। यदि चक्रवृद्धि ब्याज की दर 5% प्रति वर्ष है, तो वह राशि क्या है?


Option”C” is correct

A = Rs. 4410, r = 5% and time = 2 years

As we know,

A = P (1 + r/100)t

⇒ 4410 = P (1 + 5/100)2

⇒ 4410 = P × 21/20 × 21/20

⇒ P = 4410 × 20/21 × 20/21

⇒ P = 4000

Again,

A = Rs. 3150, r = 5% and time = 1 years

As we know,

A = P (1 + r/100)1

⇒ 3150 = P (1 + 5/100)2

⇒ 3150 = P × 21/20

⇒ P = 3150 × 20/21

⇒ P = 3000

∴ Total sum = 4000 + 3000 = 7000

Short trick:

If rate 5%, then

Ratio of A to P after 2 years = 202 : 212 = 400 : 441

441 unit = 4410

1 unit = 4410/441 = 10

Hence, 40 unit  = 400 × 10 = 4000

Again

Ratio of A to P after 1 year = 20 : 21

21 unit = 3150

1 unit = 150

Hence, 20 unit = 150 × 20 = 3000

∴ Total sum = 4000 + 3000 = 7000

90. A sum of money is invested at 20% compound interest (compounded annually). It would fetch Rs. 723 more in two years if interest is compounded half-yearly. The sum is

एक राशि का निवेश 20% चक्रवृद्धि ब्याज (सालाना समायोजित) पर किया जाता है। अगर ब्याज छमाही के हिसाब से समायोजित किया जाए तो दो साल में यह 723 रुपये से अधिक होगा। मूलधन क्या है?


Option”B” is correct

Rate = 20%, time = 2 year and if interest compounded yearly, then

Total interest rate at the end of 2 years = 20 + 20 + (20 × 20)/100 = 40 + 4 = 44%

If interest rate compounded half-yearly, then

Rate = 20/2 = 10%

Total interest rate for first 2 years = 10 + 10 + (10 × 10)/100 = 21%

Similarly,

Total interest rate for last 2 years = 10 + 10 + (10 × 10)/100 = 21%

Total interest rate for 4 years = 21 + 21 + (21 × 21)/100 = 42 + 4.41 = 46.41%

Difference of interest rate = 46.41% – 44% = 2.41%

⇒ 2.41% = 723

⇒ 1% = 723/2.41

⇒ 1% = 300

⇒ 100% = 30,000