In how many years a sum of Rs. 3000 will yield an interest of Rs. 1080 at 12% per annum simple interest?

A sum becomes 5 times of itself in 3 years at compound interest (interest is compounded annually). In how many years will the sum becomes 125 times of itself?

The simple interest and the true discount on a certain sum for a given period and at a given rate are 25 and 20 respectively. The sum is 

The difference between the compound interest and simple interest of a certain sum of amount is rupees 256.40 for 4 years at 10% rate per annum. Find the sum of money?

A sum of money amounts to 5,200 in 5 years and to 5,680 in 7 years at simple interest. The rate of interest per annum is-

The amount of Rs 400 becomes Rs 480 in 4 years. If the rate of interest is increased by 2 percent, how much will it be?

An amount doubles itself in 5 years simple interest. What is the rate of interest per year?

A sum of money becomes 3 times in 12 years. In how many years it will become 5 times at the same rate of simple interest?