A sum of ₹ 3000 yields an interest of ₹ 1080 at 12% per annum simple interest in how many years ?

The difference between simple interest and compound on Rs. 1200 for one year at 10% per annum reckoned half-yearly is:

At what simple rate of interest a sum is double in 8 years?

A certain sum doubles in 7 years at simple interest. The same sum under the same interest rate will become 4 times in how many years.:

What equal installment of annual payment will discharge a debt which is due as ₹ 848 at the end of 4 years at 4 % per annum simple interest? 

Rs. 1,080 invested for 3 months gave an interest of Rs. 27. The simple rate of interest per annum was :

A sum of Rs.1600 gives a simple interest of Rs.252 in 2 years and 3 months. The rate of interest per annum is 

A principal increase by 50 percent in five years at the rate of simple interest. What will be the compound interest for 3 years at Rs 20,000 with the same interest rate?