What sum will give ₹ $244$ as the difference between simple interest and compound interest at $10 \%$ per annum in $1 \frac{1}{2}$ years,compounded half-yearly?

The least number of completed years in which a sum of money put out at $20 \%$ $C.I.$ will be more than doubled is

What will be the compound interest on a sum of ₹ $25000$ after $3$ years at the rate of $12 \%$ per annum?

If a sum of money compounded annually becomes $1.44$ times of itself in $2$ years,then the rate of interest per annum (in $\%$) is:

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

$A$ bank offers $5 \%$ compound interest calculated on a half-yearly basis. $A$ customer deposits $Rs. 1600$ each on $1^{st}$ January and $1^{st}$ July of a year. At the end of the year,the amount (in $Rs.$) he would have gained by way of interest is: