What will happen if interest is compounded quarterly? How many conversion periods will be there? What about the quarter-year rate? How much will it be of the annual rate? 

A sum of $₹ 2500$ becomes $₹ 8100$ in $2$ years at a certain rate of compound interest. What will be the sum (in $₹$) after $4$ years?

How long will a sum of money take to double, if it is invested at $9.09\%$ p.a. simple interest?

What is the ratio of simple interest earned on certain amount at the rate of $12\%$ p.a. for $9$ years and that for $12$ years ? 

1. $1:2$
2. $2:3$
3. $3:4$
4.$4:5$

On a certain principal, simple interest amounts to Rs. 1000 in 1 year at the rate of 10% p.a. What will be the effective rate of interest if the same is compounded on a half-yearly basis?

1. 10.10
2. 10.15
3. 10.20
4. 10.25

What will be the compound interest on a sum of Rs. 160000 for 2 years at the annual rate of 10%, if the interest is compounded half yearly?

What will $₹40,000$ amount to in $2$ years at the rate of $20\%$ p.a., if interest is compounded yearly?