Aptitude - Simple Interest

Exercise : Simple Interest - General Questions
1.
A sum of money at simple interest amounts to Rs. 815 in 3 years and to Rs. 854 in 4 years. The sum is:
Rs. 650
Rs. 690
Rs. 698
Rs. 700
Answer: Option
Explanation:

S.I. for 1 year = Rs. (854 - 815) = Rs. 39.

S.I. for 3 years = Rs.(39 x 3) = Rs. 117.

Principal = Rs. (815 - 117) = Rs. 698.


2.
Mr. Thomas invested an amount of Rs. 13,900 divided in two different schemes A and B at the simple interest rate of 14% p.a. and 11% p.a. respectively. If the total amount of simple interest earned in 2 years be Rs. 3508, what was the amount invested in Scheme B?
Rs. 6400
Rs. 6500
Rs. 7200
Rs. 7500
None of these
Answer: Option
Explanation:

Let the sum invested in Scheme A be Rs. x and that in Scheme B be Rs. (13900 - x).

Then, x x 14 x 2 + (13900 - x) x 11 x 2 = 3508
100 100

28x - 22x = 350800 - (13900 x 22)

6x = 45000

x = 7500.

So, sum invested in Scheme B = Rs. (13900 - 7500) = Rs. 6400.

Video Explanation: https://youtu.be/Xi4kU9y6ppk


3.
A sum fetched a total simple interest of Rs. 4016.25 at the rate of 9 p.c.p.a. in 5 years. What is the sum?
Rs. 4462.50
Rs. 8032.50
Rs. 8900
Rs. 8925
None of these
Answer: Option
Explanation:
Principal
= Rs. 100 x 4016.25
9 x 5
= Rs. 401625
45
= Rs. 8925.

4.
How much time will it take for an amount of Rs. 450 to yield Rs. 81 as interest at 4.5% per annum of simple interest?
3.5 years
4 years
4.5 years
5 years
Answer: Option
Explanation:

Time = 100 x 81 years = 4 years.
450 x 4.5

Video Explanation: https://youtu.be/WdBzN0Sj8jc


5.
Reena took a loan of Rs. 1200 with simple interest for as many years as the rate of interest. If she paid Rs. 432 as interest at the end of the loan period, what was the rate of interest?
3.6
6
18
Cannot be determined
None of these
Answer: Option
Explanation:

Let rate = R% and time = R years.

Then, 1200 x R x R = 432
100

12R2 = 432

R2 = 36

R = 6.

Video Explanation: https://youtu.be/TjjI4iRkzT0