The difference between the compound interest and simple interest on a certain sum at $5 \%$ per annum for $2$ years is ₹ $1.50$. The sum is (in ₹):

The compound interest on a certain sum for $2$ years at $10 \%$ per annum is ₹ $525$. The simple interest (in ₹) on the same sum for double the time at half the rate per cent per annum is

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 $\%$).

What is the difference between the compound interests (in ₹) on ₹ $5000$ for $1 \frac{1}{2}$ years at $4 \%$ per annum compounded yearly and half-yearly?

The difference between the compound and simple interest on a sum of money for $2$ years at $6 \frac{1}{4} \%$ per annum is $Rs. 10$. The sum (in $Rs.$) is

If a sum of money at compound interest amounts to thrice itself in $3$ years,then in how many years will it be $9$ times itself?