Given
$20,000 at 4% compounded quarterly for 3/4 of a year
To find the interest amount.
Now,
The principal amount is $20,000, rate of interest r is 4% and time taken t is 3/4 of a year.
Then, the formula for amount compounded quarterly is given by,

Then,

Hence, the amount is Rs. 22497.28.
Therefore, the compound interest is given by,

Hence, the compound interest is Rs. 2497.28.