Aptitude - Compound Interest - Discussion

Discussion Forum : Compound Interest - General Questions (Q.No. 4)
4.
What is the difference between the compound interests on Rs. 5000 for 1 years at 4% per annum compounded yearly and half-yearly?
Rs. 2.04
Rs. 3.06
Rs. 4.80
Rs. 8.30
Answer: Option
Explanation:

C.I. when interest
compounded yearly    
= Rs. 5000 x 1 + 4 x 1 + x 4
100 100
= Rs. 5000 x 26 x 51
25 50
= Rs. 5304.

C.I. when interest is
compounded half-yearly
= Rs. 5000 x 1 + 2 3
100
= Rs. 5000 x 51 x 51 x 51
50 50 50
= Rs. 5306.04

Difference = Rs. (5306.04 - 5304) = Rs. 2.04

Discussion:
85 comments Page 5 of 9.

Deepak said:   9 years ago
How to decide 4% rate?

SAIKUMAR said:   9 years ago
Compounded yearly:
P = 5000,
R = 4% -----> 200,
So, 5000 + 200 = 5200,
R = 2% -----> 104,
Then total = 5200 + 104 = 5304.

Compounded half-yearly:
P = 5000,
R = 2% -----> 100,
Then, 5000 + 100 = 5100,
R = 2% -----> 102,
Then, 5100 + 102 = 5202,
R = 2% -----> 104.04,
Total = 5202 + 104.04 = 5306.04.

And finally, 5304 - 5306.04 = 2.04.
(2)

Ronak soni said:   9 years ago
(1+2/100)^3 in this, why this cube is taken in half yearly?

Lalit Rawat said:   9 years ago
When interest is compounded half yearly and time is in fraction.

A = P(1 + r/2 * 100)^2n.

Varun said:   9 years ago
Just using a formula of the amount when the interest is compound half yearly, ie time =2n here n = 3/2 then,

2n = 3/2 * 2= 3.

Akshay said:   9 years ago
Direct formula for finding the amount of compound interest.

A = P( 1 + R*t/100)^n/t.

Where,
A : Amount ( principle + interest).
P : principle amount.
R : rate of interest in %.
t : number of years for interested is compounded.
n : number of years.

In above example,
For the half year compounded t=1/2.

Try this method.
Thanks.

INDRANIL said:   9 years ago
If there is any shortcut formula for this? Please assist.

Chirpy said:   9 years ago
How does 26/25 & 51/50 come in the 2nd step?

Ritesh said:   10 years ago
Here formula used for amount but question is for C.I? How?

So please check it.

Mohit said:   10 years ago
Any short method without this formula?


Post your comments here:

Your comments will be displayed after verification.