The simple interest accrued on a certain principal is ₹ $1200$ in $4$ years at the rate of $8 \%$ per annum. What would be the simple interest (in ₹) accrued on thrice of that principal at the rate of $6 \%$ per annum in $3$ years?

Dalajit lent ₹ $10800$ to Jaabir for $3$ $years$ and ₹ $7500$ to Kabir for $2$ $years$ on simple interest and received ₹ $1422$ in all from both of them as interest. 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 what time (in $years$) will a sum of money double itself at the rate of $20 \%$ per annum simple interest?

$A$ man buys a watch for ₹ $1950$ in cash and sells it for ₹ $2200$ at a credit of $1$ $year$. If the rate of interest is $10 \%$ $p.a.$,what is his profit or loss?

If the amount obtained by Mahesh by investing ₹ $1500$ for $2 \frac{1}{2}$ years at the rate of $8 \%$ $p.a.$ is equal to the amount obtained by Suresh by investing a certain sum for $2$ years at $5 \%$ $p.a.$ simple interest,then the sum invested by Suresh is