$A$ sum of money placed at compound interest doubles itself in $5$ years. It will amount to eight times itself at the same rate of interest in (in $years$):

What will be the amount (in ₹) received on $25000$ at the rate of $20 \%$ per annum compounded yearly for $4$ years?

$A$ sum of money lent at compound interest amounts to ₹ $1460$ in $2$ years and to ₹ $1606$ in $3$ years. The rate of interest (in $\%$) per annum is:

$A$ man borrows money at $3 \%$ per annum interest payable yearly and lends it immediately at $5 \%$ interest (compound) payable half-yearly and thereby gains ₹ $330$ at the end of the year. The sum borrowed (in ₹) is

Abhinav invested a certain amount at the rate of $8$ $p.c.p.a.$ for $5$ years and obtained a $SI$ of $Rs. 3800$. Had he invested the same amount at the same interest rate for $2$ years,how much amount (in $Rs.$) would he have obtained as $CI$ at the end of $2$ years?

If the ratio of $C.I.$ and $S.I.$ interest for the same principal and rate of interest for $2$ years is $1.2,$ find the rate of interest (in $\%$).