Unplugged Practice Test: Logical Reasoning Set 2, Question 18 (Parallel Flaw)
Taking the test? Finish it first. This page shows the answer.
- Parallel Flaw questions ask you to match the argument's flawed structure.
- Predict what a correct answer needs to do before you read the choices.
- Every question on this test is original, written to the same logical skeletons as real questions, and Steve checked every one himself before release.
The question
Museums that publish a printed catalog of their holdings take in nearly 3 times as many loan requests from other institutions as museums with no catalog take in. So if your museum wants more loan requests, it should publish a catalog of its holdings.
18. The flawed reasoning in the argument above is most similar to that in which one of the following?
- (A)Buying a second projector usually lets a film society keep its screenings running on schedule. So if your film society holds screenings, it should buy a second projector.
- (B)Swimming laps regularly both lowers a person's resting heart rate and builds shoulder strength. So if you want a lower resting heart rate, you should work on your shoulder strength.
- (C)People who own more than 6 bicycles ride far more miles per year than people who own fewer. So if you want to ride more miles per year, you should acquire more bicycles.
- (D)Households that keep several pets usually find an automatic feeder well worth having. So if your household keeps several pets, you should buy an automatic feeder.
- (E)Fundraisers send mail appeals to people who have given by mail before. So if you want less mail from fundraisers, you should not give by mail.
CWhy (C) is correct
Museums with a printed catalog take in nearly 3 times as many loan requests as museums without one, and the argument jumps from that correlation straight to a recommendation: publish a catalog to draw more requests. It never rules out that museums already drawing more interest are the ones likely to publish catalogs in the first place. (C) repeats that exact move: owning more than 6 bicycles correlates with riding far more miles, and the argument advises acquiring more bikes to ride more, ignoring that people who already ride a lot may be the ones who end up owning more bikes.
Why the other answers are wrong
AWhy (A) is wrong
(A) cites an actual causal benefit, a second projector genuinely helping a schedule run on time, not a bare correlation, so it doesn't match.
BWhy (B) is wrong
(B) confuses 2 separate effects of one cause, swimming, for each other, a different flaw.
DWhy (D) is wrong
(D) rests on a feeder genuinely being worth having, not on a suspect correlation.
EWhy (E) is wrong
(E) tracks a real causal link, appeals following past mail giving, and reasons soundly, not the flawed pattern here.
Common questions
What type of question is this?
Parallel Flaw. Parallel Flaw questions ask you to match the argument's flawed structure.
How do I get better at Parallel Flaw questions?
Predict the answer before reading the choices. The free LSAT cheat sheet lists the wrong-answer patterns to watch for on every type.
