Practice MCQ Questions and Answer on Compound Interest

The compound interest on Rs. 4,000 after 3 year is Rs. 630.50. Then the rate of interest compounded yearly is:

(A) 7%
(B) 5%
(C) 8%
(D) 6%

Solution: $\begin{aligned} 4630.50 = 4000 {(1 + \frac{R}{100})}^{3} \\ 9261 = 8000 {(1 + \frac{R}{100})}^{3} \\ \frac{9261}{8000} = {(1 + \frac{R}{100})}^{3} \\ {(\frac{21}{20})}^{3} = {(1 + \frac{R}{100})}^{3} \\ \frac{21}{20} = (1 + \frac{R}{100}) \\ \frac{1}{20} = \frac{R}{100} \\ R = 5 \end{aligned}$

The compound interest on a certain sum for 2 years at 10% per annum is Rs. 525. The simple interest on the same sum for double the time at half the rate percent per annum is:

(A) Rs. 400
(B) Rs. 500
(C) Rs. 600
(D) Rs. 800

Solution: $\begin{aligned} Let the sum be Rs. P \\ Then, P {(1 + \frac{10}{100})}^{2} - P = 525 \\ \Rightarrow P [{(\frac{11}{10})}^{2} - 1] = 525 \\ \Rightarrow P = \frac{525 \times 100}{21} = 2500 \\ ∴ Sum = R s . 2500 \\ So, S.I. = R s . (\frac{2500 \times 5 \times 4}{100}) \\ = R s . 500 \end{aligned}$

A sum of money is compound interest became doubles itself in 15 years. It will become eight times of itself in = ?

(A) 45 years
(B) 48 years
(C) 54 years
(D) 60 years

Solution: $\begin{aligned} P {(1 + \frac{R}{100})}^{15} = 2 P \\ \Rightarrow {(1 + \frac{R}{100})}^{15} = 2 \\ Let P {(1 + \frac{R}{100})}^{n} = 8 P \\ \Rightarrow {(1 + \frac{R}{100})}^{n} = 8 = 2^{3} = {{(1 + \frac{R}{100})}^{15}}^{3} \\ \Rightarrow {(1 + \frac{R}{100})}^{n} = {(1 + \frac{R}{100})}^{45} \\ \Rightarrow n = 45 \\ ∴ Required time = 45 years \end{aligned}$

An amount of Rs. 10000 becomes Rs. 14641 in 2 years if the interest is compounded half yearly. What is the rate of compound interest p.c.p.a. ?

(A) 10%
(B) 12%
(C) 16%
(D) 20%

Solution: $\begin{aligned} Let the rate be R% p .a . \\ Then, \\ 10000 {(1 + \frac{R}{2 \times 100})}^{4} = 14641 \\ \Rightarrow {(1 + \frac{R}{200})}^{4} = \frac{14641}{10000} = {(\frac{11}{10})}^{4} \\ \Rightarrow 1 + \frac{R}{200} = \frac{11}{10} \\ \Rightarrow \frac{R}{200} = \frac{1}{10} \\ \Rightarrow R = 20% \end{aligned}$

The compound interest on a certain sum of money for 2 years at 5% per annum is Rs 410. The simple interest on the same sum at the same rate and for the same time is = ?

(A) Rs. 400
(B) Rs. 300
(C) Rs. 350
(D) Rs. 405

Solution: $\begin{aligned} Rate of interest 5 % \\ = \frac{1}{20} \\ Let principal \\ = {(20)}^{2} = 400 units \\ \Rightarrow Total compound interest \\ 41 Units \to Rs. 410 \\ 1 Units \to Rs. 10 \\ 400 Units \to Rs. 400 \\ Total simple interest \\ = Rs. 400 \end{aligned}$ Alternate Total compound interest for 2 years at 5% p.a. $\begin{aligned} = 5 + 5 + \frac{5 \times 5}{100} = 10.25 % \\ Total simple interest \\ = 10 % \\ \Rightarrow 10.25 % \to 410 \\ \Rightarrow 10 % \to 400 \\ Simple interest \\ = Rs . 400 \end{aligned}$

A money lender borrows money at 4% per annum and pays the interest at the end of the year. He lends it at 6% per annum compound interest compounded half yearly and receives the interest at the end of the year. In this way, he gains Rs. 104.50, a year. The amount of money be borrows, is ?

(A) Rs. 4500
(B) Rs. 5000
(C) Rs. 5500
(D) Rs. 6000

Solution: $\begin{aligned} Let the sum Rs . x \\ Then, \\ C .I . when compounded half yearly \\ = Rs . [x \times {(1 + \frac{3}{100})}^{2} - x] \\ = Rs . (\frac{10609}{10000} x - x) \\ = Rs . (\frac{609 x}{10000}) \\ C .I . when compounded yearly \\ = Rs . [x \times (1 + \frac{4}{100}) - x] \\ = Rs . (\frac{26 x}{25} - x) \\ = Rs . \frac{x}{25} \\ ∴ \frac{609 x}{10000} - \frac{x}{25} = 104.50 \\ \Rightarrow \frac{209 x}{10000} = 104.50 \\ \Rightarrow x = (\frac{104.50 \times 10000}{209}) \\ \Rightarrow x = 5000 \end{aligned}$

A certain some of money and Rs. 2420 in 2 years and Rs. 2662 in 3 years at same rate of compound interest, compounded annually. The rate of interest per annum is = ?

(A) 6%
(B) 8%
(C) 9%
(D) 10%

Solution: $\begin{aligned} Amount after three years \\ = Rs. 2662 \\ Amount after two years \\ = Rs. 2420 \\ Net interest earned in the 3^{rd} year \\ = 2662 - 2420 \\ = Rs . 242 \\ Rate of interest (r) \\ = \frac{242}{2420} \times 100 = 10% \end{aligned}$ (∴ 2nd year's amount is principal for 3rd year)

A person borrowed some money on compound interest and returned it in 3 equal annual instalments. If the rate of interest is 15% per annum and the annual instalment is Rs. 12,167, then find the sum borrowed.

(A) Rs. 27,780
(B) Rs. 28,530
(C) Rs. 25,780
(D) Rs. 26,970

If the compound interest on a certain sum for two years at 12% per annum is Rs. 2544, the simple interest on it at the same rate for 2 years will be = ?

(A) Rs. 2400
(B) Rs. 2500
(C) Rs. 2480
(D) Rs. 2440

Solution: $\begin{aligned} Rate = 12 % \\ Time = 2 years \\ Effective rate of CI for 2 years \\ = 12 + 12 + \frac{12 \times 12}{100} \\ = 25.44 % \\ Effective rate of SI for 2 years \\ = 12 \times 2 = 24 % \\ According to question, \\ Required SI \\ = \frac{2544}{25.44} \times 24 = Rs. 2400 \\ Required sum \\ = Rs. 2400 \end{aligned}$

10.

Simple interest on a certain sum of money for 3 years at 8% per annum is half the compound interest on Rs. 4000 for 2 years at 10% per annum. The sum placed on simple interest is:

(A) Rs. 1550
(B) Rs. 1650
(C) Rs. 1750
(D) Rs. 2000

Solution: $\begin{aligned} C .I . = R s . [4000 \times {(1 + \frac{10}{100})}^{2} - 4000] \\ = R s . (4000 \times \frac{11}{10} \times \frac{11}{10} - 4000) \\ = R s . 840 \\ ∴ Sum = R s . (\frac{420 \times 100}{3 \times 8}) \\ = R s . 1750 \end{aligned}$

«
1
2
3
4
5
6
7
8
9
10
...
15
16
Next ›
Last »

Indian Polity Mcq IAS GK Question India GK World GK GK questions GK Quiz Biology GK Science GK Physics GK Chemistry GK General Awareness Computer GK Political GK Indian Political GK Economics GK History GK Sports GK Geography GK Teaching Aptitude GK CTET/TET GK B Ed Entrance GK Banking GK SSC GK UPSC GK Indian Army GK Hindi Grammar GK Hindi Grammar MCQ Reasoning questions Bihar GK Rajasthan GK Jharkhand GK MP GK UP GK Chhattisgarh GK Haryana GK HP GK Maharashtra GK Electronics GK Agriculture GK States/Capitals GK Books Name & Author Arthimetic Verbal Reasoning Non Verbal Reasoning English

Practice MCQ Questions and Answer on Compound Interest

General Knowledge