What is $C.I.$ (in $Rs.$) on $Rs. 7500$ for $4$ years if the rate of interest is $10 \%$ p.a. for the first $2$ years and $20 \%$ p.a. for the next $2$ years?

The compound interest on a sum of money for $3$ years at $5 \%$ per annum is ₹ $1324.05$. What is the simple interest (in ₹)?

Find the present worth (in ₹) of ₹ $9261$ due $3$ years hence at $5 \%$ per annum compounded yearly.

Nikita invested ₹ $8000$ for $3$ years at $5 \%$ $C.I.$ in a post office. If the interest is compounded once in a year,what sum (in ₹) will she get after $3$ years?

What will be the amount (in ₹) if a sum of ₹ $5000$ is placed at compound interest for $3$ years,while the rate of interest for the first,second,and third years is $2\%$,$3\%$,and $4\%$ per annum,respectively?

The simple interest on a certain sum of money for $3$ years at $8 \%$ per annum is half the compound interest on ₹ $4000$ for $2$ years at $10 \%$ per annum. The sum placed on simple interest (in ₹) is