The population of a city increases by 4% per year but due to migration it decrease by 1% per years. What will be the percentage increase in population in 3 years?
Select.
A) 9 % B) 9.27 % C) 27 % D) 12 % E) none of these

Rationale: "actual increase in population = 3 % let , earlier population = 100 then the population after 3 years = 100 ( 1 + 3 / 100 ) ^ 3 = 109.2727 ∴ required percentage = 9.27 % answer : b"
Answer: B