Find the difference (in $Rs.$) between $C.I.$ and $S.I.$ on $Rs. 13000$ at $4 \%$ per annum for $3$ years.

An amount of money at compound interest grows up to $Rs. 3840$ in $4$ $years$ and up to $Rs. 3936$ in $5$ $years$. Find the rate of interest (in $\%$)?

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:

If the ratio of $C.I.$ and $S.I.$ interest for the same principal and rate of interest for $2$ years is $1.2,$ find the rate of interest (in $\%$).

In how many years will ₹ $2,000$ yield ₹ $662$ as compound interest at $10 \%$ per annum compounded annually?

If the compound interest on a certain sum for $3$ years at $5 \%$ p.a. exceeds the simple interest on the same sum for the same time and at the same rate by $Rs. 183$,find the sum (in $Rs.$).