# Quantitative Aptitude Questions and Answers - Simple Interest

11. The difference between simple interest and compound on Rs. 1200 for one year at 10% per annum
reckoned half-yearly is:

A. Rs. 2

B. Rs.3

C. Rs.4

D. Rs. 5

View Answer

Ans : B

Explanation: Solution: SI =Rs. (1200 ×10×1)/100= Rs. 120

CI = Rs. [ 1200×(1+5/100) ^2 - 1200] = Rs.123

So CI-SI = Rs. 3

12. A and B each borrowed equal sums for 3 years at the rate of 5% simple and compound interest
respectively. At the time of repayment B has to pay Rs. 76.25 more than A. The sum borrowed and the
interest paid by A (in Rs.) is:

A. Rs. 10,000, Rs. 1,500

B. Rs. 11,000, Rs. 1,100

C. Rs. 10,000, Rs. 1,400

D. Rs. 9,000, Rs. 200

View Answer

Ans : A

Explanation: CI-SI=Rs. 76.25

p[1+r/100]^n-p-PRN/100=76.25

p[1+5/100]^3-p-p*5*3/100=76.25

p[21/20*21/20*21/20]-p-15p/100=76.25

9261p-8000p-1200p/8000=76.25

61p=8000*76.25

p=10000

SI paid by A=PNR/100=10000*5*3/100=Rs. 1500

13. Equal amounts of each Rs. 43,892 is lend to two persons for 3 years. One at the rate of 30% S.I. and
second at the rate of 30% C.I. annually. By how much percent the C.I. is greater than the simple interest
received in this 3 years duration?

A. 0.31

B. 0.32

C. 0.33

D. 0.34

View Answer

Ans : C

Explanation: SI=43892*30*3=43892[9/10]|

CI=43892[(1+30/100)^3-1]=43892(2197-1000/1000)=43892(1197/1000)

CI-SI=43892(297/1000)

Desired%=43892(297/1000)/43892(900/1000) = 33%

14. The compound interest on a certain sum for 2 years is Rs. 756 and S.I. is Rs. 720. If the sum is invested
such that the S.I. is Rs. 1296 and the number of years is equal to the rate per cent per annum, Find the rate
of interest?

A. 0.05

B. 0.08

C. 0.07

D. 0.06

View Answer

Ans : D

Explanation: CI for 2 years = Rs. 756

SI for 2 years = Rs. 720

36/360 * 100 = 10%

P for first year = 3600

P*x*x/100 = 1296

x = 6%

15. The compound interest on a certain sum for 2 years at a certain rate of interest is Rs 1025 and Simple
Interest on the same sum, same time and same rate of interest is Rs 1,000. Then find the C.I for same sum in
3 years.

A. 1456.75

B. 1657.5

C. 1576.25

D. 1502.25

View Answer

Ans : C

Explanation: SI for 2 years = Rs 1000 =.> Si 1 year = Rs 500

In the second years Rs 25 is added in CI (1025-1000) which is 5% of 500

Hence R=5%

5%=500

100%=10000

sum=10000

CI for 3 years= RS 1576.25

16. A sum becomes triple in 6 years at S.I. The same sum will become 19 times in how many years?

A. 18 yrs

B. 36 yrs

C. 54 yrs

D. 72 yrs

View Answer

Ans : C

Explanation: SI=A-P=> A=3P as sum triples

SI=3P-P=2P in 6 years

In 19 times SI=18 P => 54 years (2:6 hence 18=54)

17. A lent Rs. 25000 to B for 4 years and Rs. 40,000 to C for 3 1/2 years and got Rs. 24,000 S.I from both B
and C. Find the rate PCPA.

A. 5

B. 10

C. 15

D. 20

View Answer

Ans : B

Explanation: 250 X 4R = 400 X (7/2) R = 2400R

=> R = 10

18. A sum of money, simple interest for 2 years is Rs 660 and compound interest is Rs 696.30, the rate of interest being the same in both cases.

A. 0.11

B. 0.08

C. 0.13

D. 0.09

View Answer

Ans : A

Explanation: Difference between C.I and S.I for 2 years = 36.30|

S.I. for one year = 330

S.I. on Rs 330 for one year = 36.30

So R% = {100*36.30}/{330*1} = 11%

19. If the simple interest on a sum of money for 2 years at 5% per annum is Rs.50, what is the compound
interest on the same at the same rate and for the same time?

A. 50.75

B. 51.25

C. 52.5

D. 53.75

View Answer

Ans : B

Explanation: Simple interest for 2 years = Rs.50 ie. For 1 years Rs. 25. . In the first year the S.I and C.I are

Same ie.Rs. 25. So in the 2nd year in C.I calculated for 1 years interest also. So in second years for

Rs.25 interest is 25*5/100 = 1.25 . So total C.P = 51.25.

20.
A certain amount earns simple interest of Rs. 1750 after 7 years. Had the interest been 2% more, how much more interest would it have earned?

A. Rs. 350

B. Rs. 245

C. Rs. 290

D. Cannot be determined

View Answer

Ans : D

Explanation: We need to know the S.I., principal and time to find the rate.

Since the principal is not given, so data is inadequate.

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