$A$ sum of ₹ $1,550$ is lent out in two parts,one at $8 \%$ and another at $6 \%$. If the total annual income is ₹ $106$,find the money lent at each rate.

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

$A$ person has left an amount of ₹ $1,20,000$ to be divided between his two sons aged $14$ years and $12$ years such that they get equal amounts when each attains $18$ years of age. If the amount gets a simple interest of $5 \%$ per annum,the younger son's share at present (in ₹) is

The simple interest on a certain sum of money at the rate of $5 \%$ per annum for $8$ years is ₹ $840$. What is the rate of interest per annum for which the same amount of interest can be received on the same sum after $5$ years (in $\%$)?

Kavita invested $\frac{1}{3}$ of her money at $4 \% \text{ p.a.}$,$\frac{1}{4}$ at $3 \% \text{ p.a.}$,and the rest at $5 \% \text{ p.a.}$ She received an annual interest of $Rs. 500$ on her money. Find the total money invested (in $Rs.$).

What annual payment (in $Rs.$) will discharge a debt of $Rs. 770$ due in $5$ years,the rate of interest being $5 \%$ per annum?