4 The population of NYC is 17 million in 2008 The crude birt

4. The population of NYC is 17 million in 2008. The crude birth rate is 13 and the crude death is 8. What is the annual % rate of growth?

5. if Brazil\'s growing population of 189 million in 2008 reaches 229 million in 2025 what is the % change over this time period.

6. If itatly declining population of 58 million in 2009 reaches 54 million in 2025, what is the % change over this time period.

Please answer all question and show work.

Solution

Obviously birth rate increases and death rate decreases the population

Let us take population as of 2000 as the base = P0 = 17 million

In t years due to birth increase will be 1.13 per year and death will decrease by 1-0.08 = 0.92

Hence after t years population

P = 17(1.13)^t(0.92)^t

= 17(1.0396)^t

See that as birth rate > death rate population on the whole increasing.

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5) 189 in 2008 reaches 229 in 17 years

Percent change = 40/17 = 235.29

Increase of 235.29%

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58 to 54 in 2025

Percent change = 58-54/16 (100) = 25%

i.e. Decrease of 25%