The compound interest (in ₹) on ₹ $12000$ for $9$ months at $20 \%$ per annum,interest being compounded quarterly,is

$A$ certain sum of money invested at compound interest becomes $1.44$ times of itself in $2$ years. If twice this sum were lent at simple interest, in how many years would it double itself?

Sam invested ₹ $15000$ at $10 \%$ per annum for one year. If the interest is compounded half-yearly,then the amount (in ₹) received by Sam at the end of the year will be:

If the compound interest on a certain sum for $2$ years is ₹ $60.60$ and the simple interest is ₹ $60$,then the rate of interest per annum (in $\%$) is

$A$ sum put out at $4 \%$ compound interest payable half-yearly amounts to ₹ $6632.55$ in $1 \frac{1}{2}$ years. The sum (in ₹) is

Sonika invested an amount of ₹ $5800$ for $2$ years. At what rate of compound interest (in $\% \text{ p.a.}$) will she get an amount of ₹ $594.50$ as interest at the end of two years?