The population of a country increases
according to the model:
P = 100e0.008t where t is
time in years with t = 0 corresponding to 2000.
Find the population
in 2020. (population given in millions: 100 represent 100,000,000)
|
Solve |
Step |
| Find P using P = Poekt | Growth formula |
Identify
each part
|
|
Po=
100
|
initial amount in millions |
t =
20
|
time in years 2020 - 2000 = 20 |
k =
0.008
|
growth constant - given k = 0.008 |
| P = 100e0.008(20) » 117.4 | Growth formula |
Interpret Þ There would be about 117.4 million people in the year 2020. |
|
|
Calculator Help |
| Most calculators....use ^ or xy for exponent key |
| HINT: use these key strokes |
| 100×e ^ (0.008 ×20) [enter or =] |
| Recall e » 2.718281828459045.... |
| You will find k in using logarithms in latter sections. |