1. Record the classroom dimensions and population below. Then, calculate the area and
amount of classroom space per person.
Length = _______________ meters Width = ________________ meters
Area (length x width) = _______________ square meters
Population = _________________ people in the classroom
How much space does each person have? __________________ square meters
Hint: space = area (length x width) divided by (# of people)
2. Prediction: How much space would each person have if the number of people in the class
doubled?
3. Calculate the population density.
Population density = _______________________
Hint: population density = (# of people) divided by area (length x width)
2.
Population
density
|
(
|
population
|
)
|
= Population Density
|
|
area
|
|
for
example:
|
(
|
270,000,000 people
|
)
|
= 29 people per square kilometer
|
|
9,166,605 sq. km.
|
Birth
or Death Rates:
|
(
|
# of births or deaths per year
|
)
|
= Birth or Death Rate
|
|
total
population
|
NOTE: to find Crude Birth/Death Rates, multiply the rate
by 1,000
|
for
example:
|
(
|
23,452 births
|
)
|
= 0.025 =
2.5% birth rate
|
|
942,721 people
|
25 =
Crude Birth Rate
Finding
Population Growth Rate (r):
(This does not include immigration or emigration)
|
(
|
crude
births – crude deaths
|
)
|
=
r %
|
|
births
– deaths
|
X 100
= r %
|
|
10
|
|
total
population
|
OR
|
for
example:
|
(
|
40 - 30
|
)
|
= 1.0%
|
|
28,546 births – 24,389 deaths
|
X 100 = 0.9%
|
|
10
|
|
455,387 total people
|
Finding
the Doubling Time of a Population: THE RULE OF 70!!!
(This only applies if the population is growing exponentially)
Why 70? It is 100 x
ln(2). What does that mean? Who cares…the math works!
|
(
|
70%
|
)
|
or
|
(
|
0.7
|
)
|
=
Doubling Time (dt) in years
|
|
r
(in percent form)
|
r
(in decimal form)
|
|
for
example:
|
(
|
70%
|
)
|
or
|
(
|
0.7
|
)
|
= 10 years
|
|
7%
|
0.07
|
Finding
FUTURE Population from Growth Rate:
( initial population )
X ( growth rate ) years
= Final Population
NOTE: a growth rate of 3% is
expressed as 1.03; a growth rate of 0.25% is 1.0025
for
example: ( 468,843 people ) X ( 1.03 )10 years = 630,085 people
Population Problems – SHOW ALL WORK!!
Given the following information,
answer questions 1-4.
Schuhlsville is an island of 5000 square miles off the coast of Jabooty. There are
currently 250,000 inhabitants of the island. Last year, there were 12,000 new children born
and 10,000 people were recorded as deceased.
1. What is the current population density?
2. What
are the birth and death rates?
3. What
is the population growth rate (r)?
4. In
how many years will the population of Schuhlsville double?
Given the following information,
answer questions 5-8.
The country of Transylvania
contains 2.3 million people (vampires not included) and covers 800,000 square
miles. In the year after the last
census, there were 109,000 new children born and 111,000 people died.
5. What is the current population density?
6. What
are the birth and death rates?
7. What
is the population growth rate (r)?
8.
In how many years will the population of Transylvania double?
9. Given a 2010 world population growth rate of
about 1.3% per year, how long would it take the world’s population to double?
How
old will you be when this doubling occurs?
10. If a country doubles its population in 56
years, what has its population growth rate during that time?
