LSAT Logical Reasoning: Weaken the Argument Questions 3 — Questions and Answers
Question 1: A historian argues that Nation X's economic growth in the 1990s was caused by free trade policies adopted in 1991, since growth accelerated immediately afterward. Which most weakens this argument?
- Nation X also discovered large oil reserves in 1991, which could independently explain the growth. (Correct answer)
- Free trade is generally endorsed by economists.
- Neighboring countries also adopted free trade in the 1990s.
- Nation X's inflation rate declined in 1993.
Correct answer: Nation X also discovered large oil reserves in 1991, which could independently explain the growth.
An alternative cause—the oil discovery—emerging at the same time undermines the conclusion that free trade policies caused the growth.
Question 2: A politician argues that her city's new recycling program is working because the volume of landfill waste has decreased since its launch. Which most weakens this argument?
- The recycling program required significant public education efforts.
- A major local factory closed six months before the program launched, significantly reducing industrial waste. (Correct answer)
- Neighboring cities have not adopted similar programs.
- Landfill costs have increased nationally over the same period.
Correct answer: A major local factory closed six months before the program launched, significantly reducing industrial waste.
The factory closure provides an alternative explanation for the waste reduction that is independent of the recycling program.
Question 3: A coach argues that playing team sports builds leadership skills in teenagers because teens who play sports are more likely to hold leadership positions in school. Which most weakens this argument?
- Leadership positions are competitive and not everyone who applies receives one.
- Teens who already possess leadership traits may be more likely to both join sports teams and pursue school leadership roles. (Correct answer)
- Some sports are more competitive than others.
- Schools vary in how many leadership positions they offer.
Correct answer: Teens who already possess leadership traits may be more likely to both join sports teams and pursue school leadership roles.
Pre-existing leadership traits could cause participation in both sports and school leadership, meaning sports does not develop those traits.
Question 4: A real estate developer argues that building a new shopping mall will revitalize a depressed neighborhood because shopping malls bring foot traffic and spending to surrounding areas. Which most weakens this argument?
- Shopping malls are increasingly facing competition from online retailers, making new malls economically risky and likely to underperform. (Correct answer)
- The neighborhood has few public transportation options.
- Some local residents oppose the construction project.
- The developer has built successful malls in other cities.
Correct answer: Shopping malls are increasingly facing competition from online retailers, making new malls economically risky and likely to underperform.
If malls are economically unviable due to online competition, the expected foot traffic and spending that would revitalize the neighborhood may never materialize.
Question 5: A doctor argues that patients who maintain a positive attitude recover from surgery faster because studies show patients with positive attitudes have shorter hospital stays. Which most weakens this argument?
- Surgical techniques have improved significantly over the past decade.
- Patients who are physically healthier tend to both recover faster and maintain more positive attitudes, meaning health—not attitude—drives both outcomes. (Correct answer)
- Hospital staff may treat optimistic patients differently.
- Positive attitude is difficult to measure objectively.
Correct answer: Patients who are physically healthier tend to both recover faster and maintain more positive attitudes, meaning health—not attitude—drives both outcomes.
Better underlying health is a confounding variable that independently causes both faster recovery and a more positive outlook.
Question 6: A tech company argues that its AI hiring tool eliminates bias because it makes decisions based solely on objective job-relevant criteria without considering demographics. Which most weakens this argument?
- The AI was trained on historical hiring data that reflected past discriminatory practices, embedding those biases into its criteria. (Correct answer)
- Human interviewers also use structured criteria in some companies.
- The tool saves HR staff significant time.
- Job-relevant criteria differ across industries and roles.
Correct answer: The AI was trained on historical hiring data that reflected past discriminatory practices, embedding those biases into its criteria.
Training on biased historical data means the AI's 'objective' criteria may perpetuate past discrimination, undermining the claim of eliminating bias.
Question 7: A sociologist argues that social media use causes loneliness in young adults because surveys show heavy social media users report higher loneliness. Which most weakens this argument?
- Social media platforms are designed to maximize engagement time.
- Lonely young adults may turn to social media as a substitute for in-person connection, meaning loneliness precedes heavy use. (Correct answer)
- Young adults use social media for a variety of purposes.
- Mental health issues are increasing among young adults generally.
Correct answer: Lonely young adults may turn to social media as a substitute for in-person connection, meaning loneliness precedes heavy use.
If lonely people gravitate toward social media, the correlation reflects the effect of loneliness on usage, not the reverse.
LSAT Logical Reasoning: Weaken the Argument Questions 3
A historian argues that Nation X's economic growth in the 1990s was caused by free trade policies adopted in 1991, since growth accelerated immediately afterward.
Which most weakens this argument?