The compound interest (in ₹) on ₹ $2000$ at $5 \%$ per annum,compounded yearly,for $2$ years is

In a certain number of years,a sum of money doubles itself at $6 \frac{1}{4} \%$ simple interest per annum. The required time (in $years$) is:

The population of a state increases by $10 \%$ every year. If its population in the year $2003$ was $15$ lakhs,what was its population in the year $2005$ (in lakhs)?

On what sum will the compound interest (in ₹) for $2 \frac{1}{2}$ years at $10 \%$ per annum amount to ₹ $6352.50$?

$A$ 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?

$A$ certain sum of money (in $Rs.$) gives $Rs. 500$ as Simple Interest $(S.I.)$ at $5 \%$ per annum for $1$ year. What is the Compound Interest $(C.I.)$ on the same sum at the same rate at the end of $2$ years?