# Aptitude - Simple Interest

### Exercise :: Simple Interest - General Questions

11.

A sum of money amounts to Rs. 9800 after 5 years and Rs. 12005 after 8 years at the same rate of simple interest. The rate of interest per annum is:

 A. 5% B. 8% C. 12% D. 15%

Explanation:

S.I. for 3 years = Rs. (12005 - 9800) = Rs. 2205.

 S.I. for 5 years = Rs. 2205 x 5 = Rs. 3675 3 Principal = Rs. (9800 - 3675) = Rs. 6125.

 Hence, rate = 100 x 3675 % = 12% 6125 x 5

Video Explanation: https://youtu.be/UYwiBCRN39s

12.

What will be the ratio of simple interest earned by certain amount at the same rate of interest for 6 years and that for 9 years?

 A. 1 : 3 B. 1 : 4 C. 2 : 3 D. Data inadequate E. None of these

Explanation:

Let the principal be P and rate of interest be R%. Required ratio = P x R x 6 100
= 6PR = 6 = 2 : 3. P x R x 9 100
9PR 9

Video Explanation: https://youtu.be/GaaEDwTWc6w

13.

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. 35 B. Rs. 245 C. Rs. 350 D. Cannot be determined E. None of these

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.

14.

A person borrows Rs. 5000 for 2 years at 4% p.a. simple interest. He immediately lends it to another person at 6 % p.a for 2 years. Find his gain in the transaction per year.

 A. Rs. 112.50 B. Rs. 125 C. Rs. 225 D. Rs. 167.50

Explanation:

Gain in 2 years
 = Rs.  5000 x 25 x 2 - 5000 x 4 x 2  4 100 100
= Rs. (625 - 400)
= Rs. 225. Gain in 1 year = Rs. 225 = Rs. 112.50 2

Video Explanation: https://youtu.be/zBjcwqIcmL4