$₹ 800$ becomes $₹ 956$ in $3$ years at a certain rate of simple interest. If the rate of interest is increased by $4 \%$,what amount (in $₹$) will $₹ 800$ become in $3$ years?

Sumit lent some money to Mohit at $5 \%$ $p.a.$ simple interest. Mohit lent the entire amount to Birju on the same day at $8 \frac{1}{2} \%$ $p.a.$ In this transaction,after a year Mohit earned a profit of ₹ $350.$ Find out the sum of money (in ₹) lent by Sumit to Mohit.

The simple interest on a sum of money is $\frac{8}{25}$ of the sum. If the number of years is numerically half the rate percent per annum,then the rate percent per annum is

Nitin borrowed some money at the rate of $6 \% \text{ p.a.}$ for the first $3 \text{ years}$,$9 \% \text{ p.a.}$ for the next $5 \text{ years}$,and $13 \% \text{ p.a.}$ for the period beyond $8 \text{ years}$. If the total interest paid by him at the end of $11 \text{ years}$ is $₹ 8,160$,how much money (in $₹$) did he borrow?

Mr. Irani borrowed a sum of ₹ $10000$ from a finance company for $6$ years at $8 \%$ per annum. The amount (in ₹) returned by Mr. Irani to the finance company is:

Brinda borrowed ₹ $1000$ to build a hut. She pays $5 \%$ simple interest. She lets the hut to Ramu and receives a rent of ₹ $12 \frac{1}{2}$ per month from Ramu. In how many years would Brinda clear off the debt?