$A$ sum fetched a total simple interest of $Rs. 4016.25$ at the rate of $9 \%$ $p.a.$ in $5$ years. What is the sum (in $Rs.$)?

How many years will it take for an amount of $Rs. 600$ to yield $Rs. 120$ as interest at $10 \%$ per annum of $S.I.$?

With a given rate of simple interest,the ratio of principal and amount for a certain period of time is $4:5$. After $3$ years,with the same rate of interest,the ratio of the principal and amount becomes $5:7$. The rate of interest per annum is (in $\%$):

Girish invested some money in a bank. After $8$ years,his amount became triple. How many times of the original sum will the money become in $20$ years at simple interest?

If the interest on ₹ $800$ is more than the interest on ₹ $400$ by ₹ $40$ in $2$ years,then the rate of interest (in $\%$) per annum is:

For what sum (in ₹) will the simple interest at $R \%$ per annum for $2$ years be $R$?