The difference between the simple and compound interest on a certain sum of money for $2$ years at $4 \%$ per annum is $Rs. 4$. Find the sum (In $Rs.$)?

$A$ sum of $Rs. 1000$ after $3 \, \text{years}$ at compound interest becomes a certain amount that is equal to the amount that is the result of a $3 \, \text{year}$ depreciation from $Rs. 1728$. Find the difference between the rates (in $\%$) of $C.I.$ and depreciation? (Given $C.I.$ is $10 \% \, p.a.$)

If the simple interest on a sum of money for $2$ years at $5 \%$ per annum is ₹ $50$,what is the compound interest (in ₹) on the same sum at the same rate and for the same time?

An amount of money at compound interest grows up to ₹ $3,840$ in $4$ years and up to ₹ $3,936$ in $5$ years. Find the rate of interest (in $\%$).

The difference between the compound interest and the simple interest accrued on an amount of ₹ $18000$ in $2$ years was ₹ $405$. What was the rate of interest per cent per annum?

The difference between the simple interest and the compound interest (in ₹) on ₹ $600$ for $1$ year at $10 \%$ per annum,reckoned half-yearly is