Question

the beginning of 1975 the population of a country was 40 million and growing at a rate of 3% per year. Assume that the growth is exponential. Estimate the population of the country at the beginning of the year 2010

Answer 1

of course 80 million

Answer 2

im sorry and how did you get this?

Answer 3

plz help

Answer 4

This can be taken as a geometric progression where the population at any given year is given by \[ar ^{n-1}\]

where a is starting population and 'r' in this case is 1.03 as the population is increasing.
Now count the years, from 1975 to 2010, 35 years. So you use formula

population = \[40000000\times1.03^{35}\]
population approx 112 million

Answer 5

i got 83751117 how did you get 112 mil?

Answer 6

how did you get that? Because I've used exponential population growth method and geometric progression and got the same answer

Answer 7

ok i rechecked it ant got 1.05 and the answer was 135mil

Answer 8

ok let me g through it again. two mins :)

Answer 9

40000000*1.05^24 was 129003997.7

Answer 10

it can't be 1.05 as you gave the growth rate to be 3%

If it is 5%, then you get 40(1.05)^35 = 220 million

Check your question again. You get 135 million if the growth rate is 5% and the time period is 1975 to 2000

Answer 11

yeah the years are 1975 to 2010

Answer 12

nm

Answer 13

can you help me with this one?

Answer 14

If the population of bacteria doubles in 4 hours how long will it take for it to triple its original size