Simple Interest Problems (SI) Set 1

An Introduction

You’ll find below an extensive, well written as well as best quality study material on Simple Interest Problems (SI) under main section of Mathematics and sub-section of Arithmetic.

Our Special Initiative on Civil Service Prelim Exam oriented problem on Simple Interest (SI)

Our Arithmetic experts working on Simple Interest (SI) problems module under Numerical Ability > Mathematics > Arithmetic division to produce not only a comprehensive job oriented but also easy to learn, solve and remember best quality study materials on Simple Interest (SI) for UPSC, State PSC, SSC, IBPS competitive exams and all Government jobs/services recruitment competitive examinations.

Please scroll below to understand carefully chosen as well as selected exam oriented problems on Simple Interest (SI) Arithmetic. We’ve taken very good care of to solve the Simple Interest problems on behalf of you as it’ll be beneficial for not only you but also for all Government jobs seekers as well as competitive exam appearing candidates


Problem#1) If a sum of money doubles itself in 7 years, it becomes 5 times in how many years?

MCQ Options –

a) 24 years
b) 28 years
c) 30 years
d) 35 years

Solved answer by our arithmetic expert –

Suppose the sum is 1,

Conditionally, Re.1/- becomes Rs. 2/- in 7 years.

So, Simple Interest=>(2-1)=Re.1/-

Again S.I=> (5-1)=Rs.4/-

Required Time:- S.I is Re.1/- in 7 years

So, S.I is 4/- in = (4*7) = 28 years

Problem#2) At what rate % per annum will be a sum of money thrice in 25 years ?

MCQ Options –

a) 6%
b) 7%
c) 8%
d) 10%

Solved answer by our arithmetic expert –

Suppose the sum of money is 1/-

Conditionally Rs. 1/- becomes Rs. 3/- in 25 years.

S.I. =(3-1)=2

Then Rate= (2*100)/(1*25) = 8%  [rate= (S.I. * 100)/sum*time]

Problem#3) In how many years will a sum of money double itself at 10% per annum simple interest?

MCQ Options –

a) 10 years
b) 12 years

c) 20 years
d) 15 years

Solved answer by our arithmetic expert –

Suppose the sum of money is Re,1/-

Conditionally Re.1/- becomes Rs.2/- at 10% per annum S.I.

And the S.I. = (2-1) =1/-

Time Required = (1* 100)/(1*10)   = 10 years [Time = (S.I. *100)/ (sum * rate)]

Problem#4) A sum of money which amounts to 3/2 times of the original sum in 5 years and Rs.960/- in 6 years is:

MCQ Options –

a) Rs.900/-
b) Rs.800/-
c) Rs.700/-
d) Rs.600/-

Solved answer by our arithmetic expert –

100 become 150 in 5 years.

So, S.I=150-100=50;

Therefore, the rate is 10%.

So, principal is = (960/160) * 100 = 600/-

Problem#5) A sum of money amounts to Rs.1920/- in 5 years and Rs. 2208/- in 7 years. The rate of Simple interest per annum is:

MCQ Options –

a) 6%
b) 12%
c) 12.5%

d) 9.5%

Solved answer by our arithmetic expert –

We can say, Sum + S.I. of 7 years = 2208

Sum + S.I. of 5 years =1920

S.I. of 2 years = 288

So, S.I of 7 year => (144*7) =1008

Sum+ S.I. of 7 years = 2208

Sum =  (2208-1008) =1200

Rate = (1008* 100)/ (1200* 7) =12%



Tips & Tricks to Remember & Learn Mathematics> Arithmetic > Simple Interest Problems (SI)

Year long intense study, research & development work on Government job oriented study materials for almost all recruitment and competitive exams by Civil Service Preparation Portal ‘R&D’ team has carefully followed a line of investigation among a group of fresh graduates as well as some educated unemployed, dreaming to become successful Civil Servant by cracking either UPSC Civil Service or State level PSC Civil Service and the experts of this R&D team has discovered a secret methodology which will be very much beneficial for all Civil Service aspirants and Government Job seekers.

This is the first time we’re revealing this secret tricks online for the overall betterment of the preparation of all Civil Service students. Please find below a set of easy step by step special instruction to remember these above mentioned prelim oriented study material of Simple Interest Problems (SI) under the topic of traditional Mathematics > Arithmetic among of our numerous exam oriented study material of Civil Service General Studies –

  1. Read these best quality notes of Simple Interest Problems (SI) carefully.
  2. Try to do the problem by your own skill then write it down on your exercise copy/book instead of just copy & paste.
  3. On the way of writing down this list of important topics/points of Mathematics> Arithmetic > Simple Interest Problems (SI) – you’ve to listen the points thrice, read twice and write once.
  4. This is a special key to remember any topics on Mathematics> Arithmetic > Simple Interest Problems (SI) at one attempt and you’ll easily recall them in near future during your UPSC/PSC or other Government recruitment exams. Atleast you can choose the correct options among MCQ’s 4/5 options by doing back calculation using the techniques mentioned above in solved section of the Simple Interest Problems (SI) problems.
  5. For better result – after writing down the Study Material of Mathematics> Arithmetic > Simple Interest Problems (SI), solve same type of problems from any 10th/Secondary level reference text book.
  6. It’ll be nice to practice atleast 5-10 Simple Interest Problems (SI) of Arithmetic on daily basis. You can also opt a hobby of solving arithmetic problems or pass leisurely time by solving this type Simple Interest Problems (SI).
  7. Lastly wishing all the best to quick learn and remember this part of Mathematics> Arithmetic > Simple Interest Problems (SI) and deliver the same in your coming jobs/services recruitment competitive exams.



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