Question

If birth rate, b = 0.55 per year, death
rate, d = 0.45 per year and N = 1000,
then population after one year is
about
(A) 5500
(B) 4000
(C) 100
(D) 1100​

Answer 1

Answer:

option A is the answer hope It help

Answer 2

Answer:

The population will be 1100 after one year and the correct option is (D)

Explanation:

• A population is a changing entity. In closed population, change in population is only related to birth and death of individuals, whereas in open population, death, birth, immigration and emigration result in change of population.
• As this is the closed population, so the intrinsic rate of natural increase r will be defined as the instantaneous per capita birth rate (b) minus the instantaneous per capita death rate (d).

∴ r = b-d

Or, r = 0.55-0.45              [∵ b = 0.55 and d = 0.45]

Or, r = 0.1

And we know that the equation for exponential growth curve can be represented as

dN/dt = rN                   where, N = Population density at time t

Or, dN/dt =  0.1 x 1000

Or, dN/dt  = 100

∴ after one year the population will be 1000+100 = 1100

Hence, the correct option is (D)