LR Question 16 Explanation
QUESTION TEXT: A survey of address changes filed with post offices…
QUESTION TYPE: Strengthen
CONCLUSION: The next census (which counts all residents regardless of age) will show that Weston’s population has declined since ten years ago.
REASONING: Ten year records from the post office and driver’s license bureaus show that more households have left Weston than have entered it.
ANALYSIS: There are a few problems with the argument. One problem is that “household” can mean one person or ten people. It depends on family size.
The other problem is that post offices and drivers bureaus may not accurately track all residents. Not everyone gets a new drivers license when they move.
___________
- This is pretty vague: many people could be 1,000 or 100,000 people. Further, if they move in and out they’ll have no net effect on the population.
- It doesn’t really matter what happened during the past century. Trends can reverse themselves.
- This would weaken the argument. It shows that the population is unnaturally low.
- CORRECT. This shows that the households that left were large and the ones that stayed were small. This increases the likely population loss.
- This tells us something about each group but it doesn’t tell us how big each group is. Further, the census measures the entire population and not just adults.
More Resources for Strengthen Questions
- Intro Course lesson: This intro course lesson covers Strengthen questions.
- Mastery Seminar lesson: This LR Mastery seminar lesson covers strengthen questions.
One major flaw that I see with this question is that it makes a prediction about what will happen next year based on the past 10 years. Why isn’t that addressed as a flaw in any of the answer choices?
I feel like a better wording for this question, given the correct answer, would have been “Which one of the following, if true, EXPLAINS the population decline?”
First, an argument can have multiple flaws. But second, you’ve misunderstood what the argument was saying. Let’s say the year is 2015. So ten years ago is 2005. Next year’s census is in 2016. The argument is saying next year’s census will show that population has declined *since* 2005. So if this is population:
2005: 100,000
2015: 78,000
Then the prediction seems likely to be true, IF the data are accurate. The census is in the future, but measures the past, and so the past can help predict what the census will show.
Note: This is an old comment but I wanted to clarify the point.