Simple & Compound Interest(Quantitative Aptitude > Interest ) Questions and answers for exam Preparation

Quantitative Aptitude > Interest

SIMPLE & COMPOUND INTEREST MCQs

Compound Interest, Simple Interest, Interest (combined)

Total Questions : 1171 | Page 80 of 118 pages

Question 791. A sum of Rs. 800 becomes Rs. 956 in 3 years at a certain rate of simple interest. If the rate of interest is increased by 4%, what amount will the same sum become in 3 years ?

RS. 1042
Rs. 1025
Rs. 1024
Rs. 1052

Discuss Question

Answer: Option D. -> Rs. 1052
Answer: (d)Using Rule 1,S.I. = 956 - 800 = Rs. 156Rate = ${\text"S.I." × 100}/\text" Principal × Time"$= ${156 × 100}/{800 × 3}$ = 6.5%New rate = (6.5 + 4)% = 10.5%S.I. = ${\text"Principal × Time × Rate"/100$= ${800 × 3 × 10.5}/100$ = Rs. 252Amount = Rs.(800 + 252) = Rs.1052

Question 792. A man loses Rs.55.50 yearly when the annual rate of interest falls from 11.5% to 10%. His capital (in rupees) is

7400
3700
11100
8325

Discuss Question

Answer: Option B. -> 3700
Answer: (b)Using Rule 1,Let his capital be x.According to the question,${x × 11.5}/100 - {x × 10}/100$ = 55.50or (11.5 - 10)x = 5550or 1.5x = 5550or $x = 5550/{1.5}$ = Rs.3700

Question 793. A sum of Rs.2,400 amounts to Rs.3,264 in 4 years at a certain rate of simple interest. If the rate of interest is increased by 1%, the same sum in the same time would amount to

Rs.3,312
Rs.3,288
Rs.3,360
Rs.3,340

Discuss Question

Answer: Option C. -> Rs.3,360
Answer: (c)Using Rule 1Simple Interest (S.I.)= ${\text"Principal × Rate × Time"/100$ orS.I. = ${\text"P × R × T"/100$P = ${\text"S.I." × 100}/\text"R × T"$, R = ${\text"S.I." × 100}/\text"P × T"$, T = ${\text"S.I." × 100}/\text"P × R"$ A = P + S.I. or S.I. = A - P

Question 794. A sum of money was lent at simple interest at a certain rate for 3 years. Had it been lent at 2.5% per annum higher rate, it would have fetched Rs.540 more. The money lent was :

Rs.6472
Rs.6400
Rs.7200
Rs.6840

Discuss Question

Answer: Option C. -> Rs.7200
Answer: (c)If the sum lent be Rs. x, then${x × 2.5 × 3}/100 = 540$$x = {540 × 100}/{2.5 × 3}$ = Rs.7200Using Rule 13,$P_1 = P, R_1 = R, T_1$ = 3$P_2 = P, R_2 = R + 2.5%, T_2$ = 3S.I. = Rs.540540 = ${P × (R + 2.5%) × 3 - P × R × 3}/100$54000 = 7.5PP = $540000/75$P = Rs.7200

Question 795. Rs.800 amounts to Rs.920 in 3 years at simple interest. If the interest rate is increased by 3%, it would amount to

Rs.1,112
Rs.1,056
Rs.992
Rs.1,182

Discuss Question

Answer: Option C. -> Rs.992
Answer: (c)Using Rule 1,S.I. = Rs.(920 - 800) = Rs.120Rate = ${\text"S.I." × 100}/\text" Principal × Time"$= ${120 × 100}/{800 × 3}$ = 5% per annumNew rate = 8% per annumS.I. = ${800 × 3 × 8}/100$ = Rs.192Amount = (800 + 192) = Rs.992

Question 796. The amount Rs.2,100 became Rs.2,352 in 2 years at simple interest. If the interest rate is decreased by 1%, what is the new interest ?

Rs.220
Rs.210
Rs.252
Rs.242

Discuss Question

Answer: Option B. -> Rs.210
Answer: (b)Using Rule 1,S.I. = 2352 - 2100 = Rs.252Rate = ${\text"S.I." × 100}/\text" Principal × Time"$= ${252 × 100}/{2100 × 2}$ = 6% per annumNew rate = 5%S.I. = ${252 × 5}/6$ = Rs.210

Question 797. The simple interest on a sum of money is $8/25$ of the sum. If the number of years is numerically half the rate percent per annum, then the rate percent per annum is

8
5
4
6$1/4$

Discuss Question

Answer: Option A. -> 8
Answer: (a)Using Rule 1Simple Interest (S.I.)= ${\text"Principal × Rate × Time"/100$ orS.I. = ${\text"P × R × T"/100$P = ${\text"S.I." × 100}/\text"R × T"$, R = ${\text"S.I." × 100}/\text"P × T"$, T = ${\text"S.I." × 100}/\text"P × R"$ A = P + S.I. or S.I. = A - P

Question 798. The rate of simple interest for which a sum of money becomes 5 times of itself in 8 years is :

Discuss Question

Answer: Option D. -> 50%
Answer: (d)Principal = Rs.x (let)Amount = Rs.5xInterest = Rs.(5x - x) = Rs.4xRate = ${S.I. × 100}/\text"Principal × Time"$= ${4x × 100}/{x × 8}$ = 50% per annum

Question 799. A certain sum doubles in 7 years at simple interest. The same sum under the same interest rate will become 4 times in how many years.

Discuss Question

Answer: Option D. -> 21
Answer: (d)Case I,Interest = PrincipalRate = ${Interest × 100}/\text"Principal × Time"$= $100/7%$ per annumCase II,Interest = 3 × PrincipalTime = ${Interest × 100}/\text"Principal × Time"$= ${3 × 100}/{100/7}$ = 3 × 7 = 21 years

Question 800. At what per cent of simple interest will a sum of money double itself in 15 years?

6$2/3$%
6$1/3$%
6%
6$1/2$%

Discuss Question

Answer: Option A. -> 6$2/3$%
Answer: (a)Let principal be Rs.x.Amount = Rs.2xInterest = Rs.(2x - x) = Rs.xRate = ${S.I. × 100}/\text"Principal × Time"$= ${x × 100}/{x × 15} = 20/3$= 6$2/3%$ per annum