$A$ man invested $\frac{1}{3}$ of his capital at $7 \%$,$\frac{1}{4}$ at $8 \%$,and the remainder at $10 \%$. If the annual income is ₹ $561$,the capital (in ₹) is:

If a sum of ₹ $9$ is lent to be paid back in $10$ equal monthly instalments of ₹ $1$ each,then the rate of interest is

$₹ 800$ 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?

Rakesh borrowed ₹ $5000$ from Ganesh at simple interest. If Ganesh received ₹ $500$ more than his capital after $5$ years,then the rate of interest (in $\%$) per annum 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 $Rs.$)?

If a sum of money doubles itself in $8$ years at $S.I.$,then the rate of interest per annum (in $\%$) is: (in $.5$)