POPULATION DENSITY worksheet

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?