Find the compound interest on $Rs. 12500$ at $8 \%$ per annum for $9$ months compounded quarterly (in $Rs.$).

$A$ sum of money lent at compound interest amounts to ₹ $1460$ in $2$ years and to ₹ $1606$ in $3$ years. The rate of interest (in $\%$) per annum is:

Find the present worth (in ₹) of ₹ $9261$ due $3$ years hence at $5 \%$ per annum compounded yearly.

What sum of money (in ₹) at compound interest will amount to ₹ $650$ at the end of the first year and ₹ $676$ at the end of the second year?

$A$ sum of money at compound interest amounts to thrice itself in $3$ years. In how many years will it be $9$ times itself?

Sonika invested an amount of ₹ $5800$ for $2$ years. At what rate of compound interest (in $\% \text{ p.a.}$) will she get an amount of ₹ $594.50$ as interest at the end of two years?