What is the interest (in $Rs.$) received on a principal of $Rs. 450$ for $2$ years, if the interest received on $Re. 1$ after $4$ years at the same rate of simple interest is $Rs. 0.40$?

The sum of money that will produce ₹ $1770$ interest in $7 \frac{1}{2}$ years at $8 \%$ simple interest per annum is:

The population of a city increases at the rate of $5 \%$ $p.a.$ If the present population of the city is $370440$,then what was its population (in $lakh$) $3$ years ago?

$A$ money lender lends ₹ $400$ for $3$ $years$ to a person and ₹ $500$ for $4$ $years$ to another person at the same rate of simple interest. If altogether he receives ₹ $160$ as interest,what is the rate of interest per annum (in $\%$)?

Ram deposited a certain sum of money in a company at $12 \%$ per annum simple interest for $4$ years and deposited an equal amount in a fixed deposit in a bank for $5$ years at $15 \%$ per annum simple interest. If the difference in the interest from the two sources is $Rs. 1350$,then the sum (in $Rs.$) deposited in each case is:

$A$ man invested $\frac{1}{3}$ of his capital at $7 \%$,$\frac{1}{4}$ at $8 \%$,and the remaining at $10 \%$ rate of simple interest. If his annual income from interests is ₹ $561$,then the total capital invested (in ₹) was: