If annual growth rate of a population is 1.5-2%, what number of years will be required to double the population: (A) 70-47 years, (B) 35-47 years, (C) 35-28 years, (D) 28-23 years
Answer is B. When crude death rate is substracted from crude bih rate , the net residual is current annual grow rate , exclusive of migration. When the annual growth rate of a population is 1.5% to 2.0%, it takes 35-47 years to double the size of population. Reference : Park&;s textbook of preventive and social medicine, 23rd edition, pg no: 481, table 5