Question

“The population of a metro city experiences fluctuations in its population density over a period of time.”

1. When does the population in a metro city tend to increase?
2. When does the population in metro city tend to decline?
3. If ‘N’ is the population density at the time ‘t’, write the population density at the time ‘t + 1’.

Answer 1

1. A metro city’s population tends to grow when the pre-reproductive population greatly outnumbers the reproductive population and when the number of births, natality, and immigrants (B + I) surpasses the number of deaths, mortality, or emigration (D + E).
2. When the pre-reproductive population is smaller than the reproductive population, the number of deaths, mortality, emigration, and D + E exceeds B + I, the population of a metropolis tends to decrease.
3. Nt + 1 = Nt + [(B + 1) − (D + E)]
   Where (B = Natality, I = Immigration, D = Mortality, E = Emigration).