Find the quarterly instalment that will discharge a debt of Rs 2120 due in 1 years at 16% per annum simple interest.

40 persons take 6 days to complete a certain task, working 10 hours a day. How many hours a day will be sufficient for 30 persons to complete the same task in 10 days?

The difference between Simple Interest & Compound Interest for the fourth year is Rs 7280 at 20% per annum. What is the principal amount.

A certain number of persons can complete a work in 54 days. If there were 15 persons less, it would take 18 days more for the work to be completed. Initially, the number persons is:

A person invested Rs. 2,000 on simple interest for 7 years to obtain a total amount of Rs. 3,400 on a certain annual rate of interest. What was the rate of interest to obtain the above amount ?