The simple interest on a sum of money is \(\frac{1}{9}\) of the principal and the number of years is equal to rate percent per annum. Find the rate percent.

3\(\frac{1}{3}\)%

Principal : S.I. = 9 : 1,

Total rate of interest = \(\frac{1}{9}\) × 100 = \(\frac{100}{9}\) %

⇒ Rate of Interest × Time = Total Rate of Interest

R = T (given)

Therefore,

R × R = Total Rate of Interest

R² = \(\frac{100}{9}\)

R = \(\frac{10}{3}\) = 3 \(\frac{1}{3}\)%