Reality Math
Dot Sulock, University of North Carolina at Asheville
Life Expectancy II
1. Median Age of Death in Sub-Saharan Africa
Let’s think how the median age of death in Sub-Saharan Africa could be 5 years old, a
claim we encountered in Life Expectancy I. What is Sub-Saharan Africa anyway? Is it
big?
“Sub-Saharan Africa has just over 10% of the world’s population, but is home to
more than 60% of all people living with HIV—25.8 million.”
http://web.worldbank.org/WBSITE/EXTERNAL/COUNTRIES/AFRICAEXT/EXTAFR
HEANUTPOP/EXTAFRREGTOPHIVAIDS/0,,contentMDK:20411613~menuPK:71715
5~pagePK:34004173~piPK:34003707~theSitePK:717148,00.html
1.
(a) What is the approximate population of the world?
(b) Use your answer to (a) and the quotation below the map to estimate
the population of Sub-Saharan Africa.
(c) How does the population of Sub-Saharan Africa compare to the
population of the United States?
(d) So the US population is about what percent of world population?
1
According to this website, 25.8 million people with HIV live in Sub-Saharan Africa
which is 60% of all people with HIV.
2.
(a) Does that mean that 60% of the inhabitants of Sub-Saharan Africa
have HIV? Explain.
(b) Calculate the percent of the population of Sub-Saharan Africa with
HIV.
If 60% of the people living with HIV anywhere in the world comes to 25.8 million
people, how many people in the world have HIV in total? You could solve this with
algebra:
0.60 x = 25.8 million
3. Or you could think: if 60% of people with HIV is 25.8 million,
(a) then 20% of people with HIV must be _____ million
(b) so 100% of people with HIV must be ______ million.
2. Changes in Life Expectancy from HIV: Botswana, Uganda,
Zimbabwe, Kenya and South Africa
4. What was life expectancy in Botswana
(a) in 1988?
(b) in 2002?
(c) What was the percentage decrease in life expectancy in Botswana
from 1988 to 2002?
2
5. What was life expectancy in South Africa
(a) in 1993?
(b) in 2002?
(c) What was the percentage decrease in life expectancy in South Africa
from 1993 to 2002?
6. Which of the countries in the graph looks as if it may have a successful antiHIV program underway early on?
3. Population Pyramids: Central African Republic and the United
States
Central African Republic “Population Pyramid”
7.
(a) How many children ages 0-4 in the Central African Republic in 2008?
(b) What two 5-year periods seem most dangerous, that is, have the
biggest decreases to the next age group?
(c) The 45-49 population is approximately what percent of the 0-4
population in the Central African Republic in 2008?
(d) This tells us
(i) lots of children are being born
(ii) people are dying at a rapid rate
(iii) both (i) and (ii)
3
8. (a) How many children ages 0-4 in the United States in 2008
(b) The 45-49 population is what percent of the 0-4 population in the US in
2008?
9. When the population pyramid looks like a pyramid with a big base and small
top, what does it tell us about life expectancy in a country?
10. Two observations about the US population pyramid.
(a) In the 80+ category, the number of females is how many times the number of
males?
(b) Would funding social security be easier for a population pyramid like that of
tthe CAR or like that of the US?
4