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

$A$ part of $Rs. 38800$ is lent out at $72 \%$ per annum for six months. The rest of the amount is lent out at $5 \%$ per annum after one year. The ratio of interest after $3$ years from the time when the first amount was lent out is $5: 4$. Find the second part that was lent out at $5 \%$ (in $Rs.$).

If the simple interest on a certain sum of money is ₹ $256$ and the rate of interest per annum equals the number of years,then the rate of interest (in $\%$) is:

Albert invested an amount of $x$ rupees in a fixed deposit scheme offering $10 \%$ per annum for the $1^{\text{st}}$ year and $15 \%$ per annum for the $2^{\text{nd}}$ year and received an amount of ₹ $20,240$ after two years. What is $x$ (in ₹)?

The population of a town is $11200$. It increases by $25\%$ in the first year and decreases by $15\%$ in the second year. What is the population of the town at the end of $2$ years?

$A$ man invests ₹ $3965$ in the names of his three daughters,Neeta,Sita,and Gita,in such a way that they would receive the same amount after $2, 3,$ and $4$ years. If the rate of interest is $5 \%$ p.a.,then the amount (in ₹) invested for Neeta,Sita,and Gita is: