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

$A$ sum of money,deposited at some rate $p.c.p.a.$ of compound interest,doubles itself in $4$ years. In how many years will it become $16$ times of itself at the same rate?

$A$ man borrows $Rs. 5100$ to be paid back with compound interest at the rate of $4 \%$ p.a. by the end of $2$ years in two equal yearly instalments. How much (in $Rs.$) will be each instalment?

What would be the $C.I.$ obtained on an amount of $Rs. 12000$ at the rate of $9 \,p.c.p.a$ for $3$ years (in $Rs.$)?

If the compound interest on a sum for $2$ years at $12 \frac{1}{2} \%$ per annum is ₹ $510$,the simple interest (in ₹) on the same sum at the same rate for the same period of time is

What will be the amount (in ₹) if a sum of ₹ $5000$ is placed at compound interest for $3$ years,while the rate of interest for the first,second,and third years is $2\%$,$3\%$,and $4\%$ per annum,respectively?