If a certain sum of money amounts to ₹ $1760$ in $2$ years and ₹ $2000$ in $5$ years at simple interest,then the sum (in ₹) is:

If the simple interest on a certain sum of money after $6 \frac{1}{4}$ years is $\frac{3}{8}$ of the principal,then the rate of interest (in $\%$) per annum is

$A$ certain sum becomes $5$ times in $3$ years at simple interest. In how many years will it become $13$ times?

Rashmi lent $Rs. 600$ to Geeta for $2 \,yr$ and $Rs. 150$ to Seeta for $4 \,yr$ at the same rate of interest and received altogether $Rs. 80$ as simple interest from both. Find the rate of interest (in $\%$).

The rate of interest on a sum of money is $4 \%$ per annum for the first $2$ years,$6 \%$ p.a. for the next $4$ years,and $8 \%$ p.a. for the period beyond $6$ years. If the simple interest accrued by the sum for a total period of $9$ years is ₹ $1120$,then the sum (in ₹) is:

Mayuri took a loan at a simple interest rate of $6 \, p.c.p.a.$ in the first year,and the rate increased by $1.5 \, p.c.p.a.$ every year. If she paid $Rs. 8190$ as interest at the end of $3 \, years$,what was her loan amount (in $Rs.$)?