an amount was invested at r% per quarter. what value of r will ensure that accumulated amount at the end of one year is 1.5 times more than amount invested

Respuesta :

Answer:

[tex]r=25.7\%[/tex] will ensure that accumulated amount at the end of one year is 1.5 times more than amount invested

Step-by-step explanation:

Given: An amount was invested at r% per quarter.

To find: value of r such that accumulated amount at the end of one year is 1.5 times more than amount invested

Solution:

Let P denotes amount invested and n denotes time

As an amount (A) was invested at r% per quarter,

[tex]A=P\left ( 1+\frac{r}{400} \right )^{4n}[/tex]

According to question, accumulated amount at the end of one year is 1.5 times more than amount invested.

So,

[tex]A=1.5P+P=2.5P\\A=2.5P\\P\left ( 1+\frac{r}{400} \right )^{4n}=2.5P[/tex]

Put n = 1

[tex]P\left ( 1+\frac{r}{400} \right )^{4}=2.5P\\\left ( 1+\frac{r}{400} \right )^{4}=2.5\\1+\frac{r}{400} =(2.5)^{\frac{1}{4}}\\\frac{r}{100}=(2.5)^{\frac{1}{4}}-1\\r=100\left [ (2.5)^{\frac{1}{4}}-1 \right ]\\=25.7\%[/tex]