Question : A sum invested at a certain rate of interest per annum, compounded annually, amounts to INR 14,400 in 2 years and to INR 25,920 in 4 years. What is the sum invested?

Option 1: INR 8,200

Option 2: INR 7,500

Option 3: INR 8,500

Option 4: INR 8,000


Team Careers360 10th Jan, 2024
Answer (1)
Team Careers360 14th Jan, 2024

Correct Answer: INR 8,000


Solution : Given,
A sum invested at a certain rate of interest per annum, compounded annually, amounts to INR 14,400 in 2 years and to INR 25,920 in 4 years.
We know,
Amount after $n$ years = $P(1+\frac{r}{100})^n$, where $P$ is the principal amount and $r$ is the interest rate per annum.
After 2 years,
$14400=P(1+\frac{r}{100})^2$
⇒ $\frac{14400}{P}=(1+\frac{r}{100})^2$
After 4 years,
$25290=P(1+\frac{r}{100})^4$
⇒ $25920=P(\frac{14400}{P})^2$
⇒ $P=\frac{14400×14400}{25920}$
⇒ $P=8000$
Hence, the correct answer is INR 8000.

Know More About

Related Questions

TOEFL ® Registrations 2024
Apply
Accepted by more than 11,000 universities in over 150 countries worldwide
Manipal Online M.Com Admissions
Apply
Apply for Online M.Com from Manipal University
GRE ® Registrations 2024
Apply
Apply for GRE® Test now & save 10% with ApplyShop Gift Card | World's most used Admission Test for Graduate & Professional Schools
View All Application Forms

Download the Careers360 App on your Android phone

Regular exam updates, QnA, Predictors, College Applications & E-books now on your Mobile

150M+ Students
30,000+ Colleges
500+ Exams
1500+ E-books