Aptitude - Compound Interest

Each of the questions given below consists of a statement and / or a question and two statements numbered I and II given below it. You have to decide whether the data provided in the statement(s) is / are sufficient to answer the given question. Read the both statements and

  • Give answer (A) if the data in Statement I alone are sufficient to answer the question, while the data in Statement II alone are not sufficient to answer the question.
  • Give answer (B) if the data in Statement II alone are sufficient to answer the question, while the data in Statement I alone are not sufficient to answer the question.
  • Give answer (C) if the data either in Statement I or in Statement II alone are sufficient to answer the question.
  • Give answer (D) if the data even in both Statements I and II together are not sufficient to answer the question.
  • Give answer(E) if the data in both Statements I and II together are necessary to answer the question.
1. 

What is the rate of compound interest?

I. 

The principal was invested for 4 years.

 II. 

The earned interest was Rs. 1491.

A. I alone sufficient while II alone not sufficient to answer
B. II alone sufficient while I alone not sufficient to answer
C. Either I or II alone sufficient to answer
D. Both I and II are not sufficient to answer
E. Both I and II are necessary to answer

Answer: Option D

Explanation:

Let Principal = Rs. P and Rate = R% p.a. Then,

Amount = Rs. P 1 + R 4
100

C.I. = P 1 + R 4 - 1
100

P 1 + R 4 - 1 = 1491.
100

Clearly, it does not give the answer.

Correct answer is (D).


2. 

What will be compounded amount?

I. 

Rs. 200 was borrowed for 192 months at 6% compounded annually.

 II. 

Rs. 200 was borrowed for 16 years at 6%.

A. I alone sufficient while II alone not sufficient to answer
B. II alone sufficient while I alone not sufficient to answer
C. Either I or II alone sufficient to answer
D. Both I and II are not sufficient to answer
E. Both I and II are necessary to answer

Answer: Option C

Explanation:

 I. Amount = Rs. 200 x 1 + 6 16
100

II. Amount = Rs. 200 x 1 + 6 16
100

Thus, I as well as II gives the answer.

Correct answer is (C).


3. 

An amount of money was lent for 3 years. What will be the difference between the simple and the compound interest earned on it at the same rate?

I. 

The rate of interest was 8 p.c.p.a.

 II. 

The total amount of simple interest was Rs. 1200.

A. I alone sufficient while II alone not sufficient to answer
B. II alone sufficient while I alone not sufficient to answer
C. Either I or II alone sufficient to answer
D. Both I and II are not sufficient to answer
E. Both I and II are necessary to answer

Answer: Option E

Explanation:

Given: T = 3 years.

 I. gives: R = 8% p.a.

II. gives: S.I. = Rs. 1200.

Thus, P = Rs. 5000, R = 8% p.a. and T = 3 years.

Difference between C.I. and S.I. may be obtained.

So, the correct answer is (E).