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?

The compound interest on $\$ 1,800$ at $10 \%$ per annum for a certain period of time is $\$ 378 .$ Find the time in years.

Rohit invested some amount at the rate of $6$ per cent pa and at the end of $3$ years he got ₹ $8730$ simple interest. How much compound interest (in ₹) he will get on same amount and same rate of interest after $2$ years.

If in a certain number of years, ₹ $3000$ amounts to ₹ $4320$ at a compound interest, in half that time ₹ $3000$ will amount to (In ₹) 

₹ $3757$ is to be divided between $A$ and $B$ such that $A's$ share at the end of $7$ years may be equal to $B$ 's share at the end of $9$ years. If rate per cent be $10 \%$ p.a. compound interest, $B$ 's share is (In ₹) 

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