Question

The present population of a village is 9261. If the annual birth rate is 17/2percent and the annual death rate is 3.5 percent, then calculate the population 3 years ago.

Answer 1

Answer:

rate difference =17/2-7/2=5%

9261=x(1+5/100)^3

x=8000

Answer 2

Answer:

5875.336 (approx)

Step-by-step explanation:

Given data

The present population of a village = 9261

The annual birth rate = 17/5 % = 8.5%      [∵ 17/2 = 8.5 ]  

The annual death rate = 3.5%    

The rate of Increase in population = rate of birth - rate of death

                                                         = 8.5% - 3.5% = 5%      

Let Population of village 3 years ago is x

Then present population of village  = $P(1+\frac{R}{100} )^{n}$  

where P = population of village 3 years ago = x    

           R = Rate of increase  = 5%

           n = number of years = 3      

We know that present population = 9261

   ⇒  $9261 = x(1+ \frac{5}{100} )^{3}$  

   ⇒  $9261 = x(\frac{105}{100} )^{3}$

   ⇒  $9261 = x(1.05)^{3}$  

   ⇒  9261 = x(1.57625)

   ⇒   x = 9261/1.57625

   ⇒   x = 5875.336