A sum of money, put at simple interest treble itself in 15 years. the rate percentage per annum is:A13 1/3%B16 2/3%C12 2/3%D20%Answer: A. 13 1/3% Read Explanation: Rate =(100 x 1) / (P x N) (100 x 2P) /(P x 15) = 40/3 = 13 1/3%Read more in App