The difference between compound and simple interest at a certain rate on $Rs. 2000$ at the end of two years is Rs. $12.8 .$ The rate of interest (In $\%$) per annum is

A bank offers $5 \%$ compound interest calculated on 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

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

If a sum of money placed at compound interest, compounded annually, doubles itself in $5$ years, then the same amount of money will be $8$ times of itself in (In $years$)

The difference between compound interest and simple interest on a sum for $2$ years at $10 \%$ per annum, when the interest is compounded annually, is ₹ $20$. If the interest were compounded half yearly, the difference in two interests (In ₹) will be

A tree increases annually by $\frac{1}{8}$ of its height. By how much will it increase (In $cm$) after $2$ years, if it stands today $64 cm$ high?