A country's population in 1991 was 59 million. In 2000 it was 63 million. Estimate the population in 2009 using the exponential growth formula.

According to this, it grows by 4 million every 9 years, so it would be 67 million in 2009

Ok so the formula for grouth is

A=Pe^ (kt)

a=amount future

P=present amount

k=constant

t=time

we have

it grew from 59 million to 63 million

in 9 years

A=63

P=59

t=9

so

63=59e^ (k9)

divide both sides by 59

(63/59) = e^ (9k)

take ln both sides

ln (63/59) = 9k

divide both sides by 9

(ln (63/59)) / 9=k

evaluate with calulator and save that value

so now we need 2009

after t years

2009-1991=18 years

t=18

P=59

k=ans

find A

A=59e^ (ans18)

A=67.27118

about 67 million

find k