A sum of money becomes 8/5 of itself in 5 years at a cartain rate of simple interest find the rate of interest

A sum of money becomes 4/3 of itself in 6 years at a cartain rate of simple interest find the rate of interest.

A sum of money becomes (41)/(40) of itself in 1/4 year at a certain rate of simple interest. The rate of interest per annum is :

A sum of money becomes (7)/(6) of itself in 3 years at certain rate of simple interest. The rate per annum is

A sum becomes three times of itself in 10 years at the rate of simple interest. What is the rate of interest per annum?

A certain sum of money doubles itself & number of years is equal to rate of interest. Find the rate of interest.