$A$ certain sum of money amounts to ₹ $918$ in $2$ $years$ and ₹ $969$ in $3.5$ $years$ at simple interest. What is the rate of interest (in $\%$ $p.a.$)?

$A$ person invested $\frac{2}{3}$ of his capital at $3 \%$,$\frac{1}{6}$ at $6 \%$,and the remainder at $12 \%$. If his annual income is $₹ 25$,then the total capital (in $₹$) is:

₹ $800$ becomes ₹ $956$ in $3$ $years$ at a certain rate of simple interest. If the rate of interest is increased by $4 \%,$ what amount (in ₹) will ₹ $800$ become in $3$ $years?$

If the simple interest on a certain sum of money for $2$ $years$ is one-fifth of the sum,then the rate of interest (in $\%$) per annum is

The simple interest on a sum of money is $\frac{1}{9}$ of the principal and the number of years is equal to the rate per cent per annum. The rate per cent per annum is equal to

In simple interest rate per annum,a certain sum amounts to ₹ $5,182$ in $2$ $years$ and ₹ $5,832$ in $3$ $years$. The principal in rupees is: