The population of a town decreases by 10% in a particular year and then increases by 15% in the next year. The population at the end of two years is : 1. (1 + 10/100)^3 (1 + 15/100) times 2. (1 - 10/100)^3 (1 + 15/100) times 3. (1 - 10/100)^3 (1 - 15/100) times 4. (1 + 10/100)^3 (1 - 15/100) times