Population Growth in Country: Calculating +1 & +4 Year Populations

In summary, population growth in a country is calculated by taking the difference between the current and previous population, dividing it by the previous population, and multiplying by 100. Factors such as birth and death rates, immigration, and economic and social factors contribute to population growth. The population growth rate is used to calculate +1 and +4 year populations by multiplying the current population by the growth rate. Population growth can be negative if there is a decrease in population. Population growth predictions are based on current trends and can be accurate to a certain extent, but unexpected events and changes can greatly impact the accuracy of these predictions.
  • #1
Peter G.
442
0
The population of a country is 15.2 million and is growing at a steady rate of 2.7% annually.
a) What was the population one year ago
b) What was the population four years ago

So I did this:

Un+1 = Un-1 * ((n-1)*0.973)

Doing so, I got for the first answer 14,789,600 but the book got 14,793,187

What did I do wrong?
 
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  • #2
Your equation is not correct. The basic relation is Un+1 = Un (1+2.7%), so for a) you can solve this to get Un as a function of Un+1.
 

Related to Population Growth in Country: Calculating +1 & +4 Year Populations

1. How is population growth in a country calculated?

The population growth in a country is calculated by taking the difference between the current population and the previous population, and then dividing that by the previous population. This number is then multiplied by 100 to get the percentage growth.

2. What factors contribute to population growth?

Population growth is affected by a variety of factors, including birth rates, death rates, immigration, and emigration. Economic and social factors can also play a role in population growth.

3. How is the population growth rate used to calculate +1 and +4 year populations?

The population growth rate is used to calculate +1 and +4 year populations by multiplying the current population by the growth rate for each respective year. For example, to calculate the +1 year population, you would multiply the current population by 1 + (growth rate/100).

4. Can population growth be negative?

Yes, population growth can be negative if there is a decrease in the population due to factors such as high death rates or significant emigration. A negative population growth rate indicates a declining population.

5. How accurate are population growth predictions?

Population growth predictions are based on current trends and factors, and can be accurate to a certain extent. However, unexpected events and changes can greatly impact population growth, making it difficult to accurately predict future populations for a country.

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