$A$ sum of money is borrowed and paid back in two annual instalments of ₹ $882$ each,with $5 \%$ compound interest per annum. The sum (in ₹) borrowed was:

If the compound interest on a certain sum for $2$ $years$ at $3 \%$ per annum is $Rs. 101.50$,then the simple interest (in $Rs.$) on the same sum at the same rate and for the same time will be:

$A$ sum of money is paid back in two annual instalments of ₹ $17,640$ each,allowing $5 \%$ compound interest compounded annually. The sum borrowed was (in ₹):

$A$ sum of money doubles in $3$ years at compound interest,compounded annually. It will become $4$ times of itself in: (in $years$)

Nikita invested ₹ $8000$ for $3$ years at $5 \%$ $C.I.$ in a post office. If the interest is compounded once in a year,what sum (in ₹) will she get after $3$ years?

The difference between simple and compound interest on a sum of $10000$ is $64$ for $2$ years. Find the rate of interest. (in $\%$)