What sum lent at $10 \%$ per year on $S.I.$ will amount to $Rs. 450$ in $2$ 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

$A$ took two loans altogether of ₹ $1200$ from $B$ and $C$. $B$ claimed $14 \%$ simple interest per annum,while $C$ claimed $15 \%$ per annum. The total interest paid by $A$ in one year was ₹ $172$. How much did $A$ borrow from $B$?

$A$ certain sum becomes ₹ $1020$ in $5$ years and ₹ $1200$ in $8$ years at simple interest. What is the value of Principal (in ₹)?

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:

Heena invests an amount of $10250$ at $4$ $p.c.p.a.$ to obtain a total amount of $Rs. 12710$ on simple interest after a certain period. For how many years did she invest the amount to obtain the total sum?