arithmetic - simple interest on a certain amount is 916 of the principal if the numbers representing the rate of interest in percent and time in years be equal then time for which the principal is lent out is - skillgun

Let sum = x. Then, S.I. = 9/16 x.
Let rate = R% and time = R years.
=> [x * R * R / 100] = 9x / 16
=> R² = 900/16
=> R = 30/4 = 7 1/2
Hence, time = 7 1/2 years.