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3 years ago

a country's population in 1990 was 242 million, in 1999 it was 244 million. estimate the population in 2013

Mathematics

1 answer:

Free_Kalibri [48]3 years ago

3 0

Answer:

247.12 million

Step-by-step explanation:

Given:

In 1990, population=242 million

In 1999, population=244 million

estimated population in 2013=?

Estimated growth is calculated by:

P(t)= Po*e^(kt)

where Po is original population

k is growth rate

t is the time in year

Now putting the values of Po=242, P(t)=244, t=9 (t=1999-1990=9) we have:

244=242e^(9k)

(244/242)=e^(9k)

ln(244/242)=9k

k=1/9ln(244/242)

k=0.00091

Now Putting k=0.00091, Po=242, and t=23 (t=2013-1990=23) we have:

P(t)=242e^(23*0.00091‬)

P(t)=247.12 million

the population in 2013 estimated to be 247.12 million!

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