At what rate percent per annum will the simple interest on a sum of money be \(\frac{2}{5}\) of the amount in 5 years?

\(\frac{40}{3}\)%

\(\frac{2 → SI}{5 → amount}\)   = P + SI               SI = \(\frac{3 × R × 5}{100}\)

      5 = P + 2                  2 = \(\frac{3 × R × 5}{100}\)

      P  = 3                      R = \(\frac{40}{3}\)%