What is the rate of simple interest per annum, when the interest of some money in 4 years will be `8/25` part of its principal?

What is the rate of simple interest per annum, when the interest of some money in 2 year will be 1/3 part of its maount ( principal along with interest )?

What is the rate of simple interest per annum, when the interest of some money in 10 yrs will be 2/5th part of it amount?

At what rate of simple interest per annum in percent the interest of a principal in 20 years will be (4)/(9) part of its amount ?

What is the rate of simple interest in percent per annum if the total interest of Rs 73,000 for 1 day is 50 paisa?

A certain principal amounts Rs2750 in 2 years at a rate of simple interest of 5% per annum. Then find the rate of simple interest in percent per annum for which the principal amounts Rs3000 in 2 years.

What will be the compound interest of Rs. 320000 in 1 year at the rate of 20% compound interest per annum when the interest is compounded at the interval of 3 months?

Find the rate of simple interest in percent per annum if the simple interest of a principal is 3/5 part of the amount in 10 years.

A person borrowed Rs 10000 from four men. If he had to repay the first man for his Rs 2000 at the rate of simple interest of 8% per annum, the second man for his Rs 4000 at the rate of simple interest of 7(1)/(2)% per annum and the third man for his Rs 1400 at a rate of simple interest of 8(1)/(2)% per annum, then in what rate of simple interest in percent per annum, the fourth man should be paid for his rest part of principal so as to the average rate of simple interest be 8.13% per annum?

At what rate of simple interest in percent per annum , a some of money becomes double in 15 years?

Ramen obtained simple interest Rs. 1600 by depositing a sum of money in a bank after 4 years at the rate of 4% simple interest per annum. If the same sum of money will be deposited in the bank at the rate of 10% compound interest per annum, then what will be the obtained compound interest?