Aptitude - Compound Interest - Discussion
Discussion Forum : Compound Interest - General Questions (Q.No. 3)
3.
There is 60% increase in an amount in 6 years at simple interest. What will be the compound interest of Rs. 12,000 after 3 years at the same rate?
Answer: Option
Explanation:
Let P = Rs. 100. Then, S.I. Rs. 60 and T = 6 years.
 R = |
 |
100 x 60 |  |
= 10% p.a. |
| 100 x 6 |
Now, P = Rs. 12000. T = 3 years and R = 10% p.a.
| C.I. |
|
|||||||||||||
|
||||||||||||||
| = 3972. |
Discussion:
94 comments Page 9 of 10.
Dibyajyoti hazarika said:
1 decade ago
I'm confused about 331 no. How it comes?
Yamini said:
1 decade ago
@Subash
There was no confusion in the given answer, here -1 is nothing but as you said Amount = {P x (1 + (R/100)^N)} - P so from this just take common as P then you get
Amount=[P x {(1 + (R/100)^N)-1}].
There was no confusion in the given answer, here -1 is nothing but as you said Amount = {P x (1 + (R/100)^N)} - P so from this just take common as P then you get
Amount=[P x {(1 + (R/100)^N)-1}].
Poorvajain said:
1 decade ago
CI=AMT-PRINCIPLE
So in this question princple is 100 and u hve taken principle 1 why so is it wrong.
So in this question princple is 100 and u hve taken principle 1 why so is it wrong.
Shalini said:
1 decade ago
I'm totally confused with these problems.
When compound interest is done by individual formulas the answer shows wrong.
When compound interest is done by individual formulas the answer shows wrong.
Anmol said:
1 decade ago
@Karthi & Vasanth: you can take any value of P instead of 100.
100 is taken just for simplicity of calculation.
Now, as there is 60% rise in principal in 6 years
therefore, Net amount after 6 years, A= P+ 60% of P =1.6P
therefore interest,I= 1.6P-P= .6P
using SI formula, I= PTR/100
so, 0.6P= P*6*R/100
-> 60=6R
-> R=10%
100 is taken just for simplicity of calculation.
Now, as there is 60% rise in principal in 6 years
therefore, Net amount after 6 years, A= P+ 60% of P =1.6P
therefore interest,I= 1.6P-P= .6P
using SI formula, I= PTR/100
so, 0.6P= P*6*R/100
-> 60=6R
-> R=10%
Vasanth said:
1 decade ago
Why we should take p value as 100?
Arush said:
1 decade ago
Thanks jeeva & subash.
Karthi said:
1 decade ago
How we get P = Rs.100 and S.I = Rs. 60 ?
Amit said:
1 decade ago
@Kusum
Simple interest formula
SI = PRN / 100
So, SI * 100 = PRN which derives new formula for R as
R = (SI * 100) / PN
Let P = Rs. 100. Then, S.I. Rs. 60 and T = 6 years.
Put all this into simple interest formula
R = (100 x 60 ) / 100 x 6 = 10% p.a.
Hope you will get it :)
Simple interest formula
SI = PRN / 100
So, SI * 100 = PRN which derives new formula for R as
R = (SI * 100) / PN
Let P = Rs. 100. Then, S.I. Rs. 60 and T = 6 years.
Put all this into simple interest formula
R = (100 x 60 ) / 100 x 6 = 10% p.a.
Hope you will get it :)
Kusum said:
1 decade ago
Any one tel me how we got R value as 10?
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers