Writing Assignment 2 Name _______________________
Due Wednesday, Sept. 28, 2005
1. The bar to the right represents 200 million people (about two thirds the size of the
population of the United States.) Suppose it measures 10 inches tall.
a. How tall is a bar that represents 1 billion (109) people, if on the same scale?
Hint: 109= ___ million = 10?*106
The bar would be ________ inches = ______ feet tall.
b. How tall is a bar that represents 10 billion people, if on the same scale?
Hint: 10 billion = 10*109= 10? = ____ million = 10?*106
The bar would be ________ inches = ______ feet tall.
2. The graph on the following page is from the United Nations Population Division
published in 1999. The width of each bar represents a time span of 10 years. For
example, the first light gray bar is the interval from 1750 to 1760. All darkly shaded
bars are predicted increments, not actual.
a. What is meant by the term population increment?
b. There are six darkly shaded bars.
What time interval is represented by the sixth gray bar? From ______ to ______.
3. What assumptions are made by this model?
4. Why does the graph of population size continue to increase even though the darkly
shaded bars decrease?
5. Mark on the graph of the population size when changes its concavity.
6. In which years is the graph concave up? From _________ to _________.
When is the above graph concave down? From _________ to _________.
7. Explain how the heights of the bars are related to the concavity of the graph of the
population size. (Check that this is consistent with your answer to Questions 5 and 6.)
100
160
170
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200
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190
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70
90
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