Question

on what sum will the compound interest at 7½ per annum for 3 years compounded annually be rs. 3101.40​

Answer 1

Answer:

2496.50471

Step-by-step explanation:

Let the sum invested be denoted by $x$

In year One:

At the beginning of the year we have $x$

Interest earned is

$\frac{7.5}{100}*x=0.075x$

Total amount at the end of year 1 is

$x+0,075x=1.075x$

In year Two:

At the beginning of the year we have $1.075x$

Interest earned is

$\frac{7.5}{100}*1.075x=0.080625x$

Total amount at the end of year 2 is

$1.075x+0.080625x=1.155625x$

In year Three:

At the beginning of the year we have $1.155625x$

Interest earned is

$\frac{7.5}{100}*1.155625x=0.086671875x$

At the end of year 3 we have

$1.155625x+0.086671875x =1.242296875x$

Now, equating this to the actual amount we get

$1.242296875x=3101.4\\x=2496.50471$