Logical reasoning PrepTest 111 · Section 4 · Question 8

Incorrect. The belief in question, and the conclusion, is about only perception and memory, so other cognitive abilities are out of scope.

Incorrect. Even if this were true, they could still serve as a good basis for comparing cognitive abilities between groups.

Incorrect. The argument doesn't care about the relationship between these cognitive abilities, just the comparison of them between age groups.

Incorrect. The conclusion cares only about whether a belief about the cognitive abilities of those over 80 is true, not why people believe it.

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Errors in Reasoning

Stimulus Summary:
Common belief: Perception and memory decline by the time you reach 80.

Study: 80-year-olds and 30-year-olds played a card game that tested perception and memory, and their abilities were equivalent.
Conclusion - The Common belief is wrong (i.e., perception and memory don't decline by 80).

Answer Anticipation:
The argument here rebuts a common belief using a study. Whenever a study is involved in an argument, we should consider a correlation/causation flaw, and a sampling flaw.

Here, however, there's no causality in the conclusion, so we can rule that flaw out. And the sample isn't called into question via any details provided—it involved 30-year-olds and 80-year-olds, with no sign that they weren't representative or the sample was too small.

Since the argument relies solely on the study, there must be something else at play here that prevents the conclusion from following from it, but we're not seeing anything that sticks out, so let's head into the answers to find something that calls the applicability of the study to the conclusion into question.

Answer Explanation:
If the level of perception and memory required to play the card game is relatively low, then these abilities could be much lower in those who are 80 compared to those who are 30 while their ability to play the game would be equivalent, as long as the 80-year-olds clear the low bar. To draw an analogy, if the test is lifting 15 pounds, then teenagers would look just as strong as Olympic weightlifters!

Key Takeaway:
Studies generally have either a correlation/causation flaw, or a sampling flaw (sometimes both!). However, when neither is present, there's usually something else wrong with the experimental design. These answers can be harder to anticipate, so definitely stay flexible as you analyze the answer choices!