GMAT · Reading inference and application · TOPIC LESSON
Infer only what the evidence licenses, and actively test whether a tempting answer could be false.
BY THE END, YOU CAN
BEFORE YOU START
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LEARN THROUGH ORIGINAL PRACTICE
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01 / UNDERSTAND & APPLY
The Neral library introduced evening collection lockers at three branches. Patrons who had reserved books could retrieve them after the desks closed, but the lockers could not accept returns. During the first month, all locker users had previously registered for the reservation service. Registration was open to any adult cardholder, although not every registered patron used a locker. The library surveyed a sample of locker users. Most respondents said that the lockers enabled them to collect a book on a day when they could not reach a desk during opening hours. The survey did not include cardholders who had never used the lockers, and it asked neither about travel distance nor about the total number of books borrowed. The director described the results as evidence that the lockers removed a scheduling obstacle for at least some existing reservation-service users. A local columnist proposed a broader conclusion: the lockers had increased reading throughout the town. The director declined to endorse that claim. A collected book need not be read, and a convenient collection method might replace a daytime visit rather than create an additional loan. The library planned to compare borrowing patterns over a longer period, while retaining the lockers in the meantime.
02 / UNDERSTAND & APPLY
An inference may restate a necessary consequence or draw a strongly supported conclusion, depending on the stem. In all cases it must stay within the passage’s evidence. “Must be true” requires necessity; “most strongly supported” can ask for the best evidential conclusion without formal certainty. Do not make every reading question artificially deductive.
A useful test for a necessity claim is to construct a world in which all stated facts remain true but the choice is false. If you can, the choice is not necessary. Plausibility alone is insufficient: a locker might encourage reading, but this passage does not establish that it did.
ORIGINAL WORKED EXAMPLE
Must the introduction of lockers have increased the total number of books borrowed?
Answer No; substitution is a counterexample.
03 / UNDERSTAND & APPLY
The passage gives locker use → prior reservation registration. It also says not every registered patron used a locker. Thus registration is necessary for the observed users but not sufficient to imply use. Reverse inference would convert “all users were registered” into “all registered people were users.”
Combine statements by aligning the same groups and period. From all first-month users being registered and the existence of surveyed users, some registered patrons used lockers. Registration being open to adults does not by itself prove all registrants were adults: “open to any adult” does not say “open only to adults.”
ORIGINAL WORKED EXAMPLE
Which follows? A: Every registered patron used a locker. B: Some registered patrons did not use a locker. C: Every adult registered. D: Only adults could register. E: No locker user visited a desk.
Answer B
04 / UNDERSTAND & APPLY
Local inferences may need two adjacent sentences; global inferences may depend on the relationship between the director’s modest claim and the columnist’s broader one. Use the minimum sufficient evidence but check that another paragraph does not qualify it.
Do not use outside knowledge about libraries, reading habits or technology adoption to fill a missing link. The task is to reason within a stipulated account. External facts may be true yet irrelevant to what this passage supports.
ORIGINAL WORKED EXAMPLE
Why does the director decline to endorse the columnist’s conclusion?
Answer The available evidence does not bridge collection convenience to increased reading across the town.
05 / UNDERSTAND & APPLY
“Most respondents” means more than half of respondents, not most town residents or even most locker users. “At least some” is deliberately weaker. Never silently replace a sample with its target population.
For EXCEPT questions first restate the task: find the one choice that lacks the specified support. Mark four options as supported and the remaining one as the exception. A negative stem changes the selection rule; it does not reverse the facts.
ORIGINAL WORKED EXAMPLE
All are stated or supported EXCEPT: A: Lockers could not accept returns. B: Some registered patrons did not use lockers. C: Survey respondents were locker users. D: The survey measured total borrowing. E: The director retained the lockers.
Answer D
06 / UNDERSTAND & APPLY
Small words often decide an inference: some/all, may/must, before/after, users/residents. A choice with “all” is not automatically wrong, but it needs universal support. A reversed choice changes direction even if its nouns match the passage.
Read a candidate as a claim you must defend. Identify the exact bridge from text to answer. If the bridge is “probably,” “usually,” or a fact you happen to know, check whether the stem permits that degree of inference and whether the passage itself supplies support.
ORIGINAL WORKED EXAMPLE
Rewrite “Most townspeople could collect books only because lockers existed” as a supported statement.
Answer Most survey respondents said lockers enabled collection on a day when they could not reach a desk during opening hours.
07 / UNDERSTAND & APPLY
Pass one: paraphrase the relevant evidence without enlarging it. Pass two: derive a candidate while preserving groups, times, quantities and modality. Pass three: try a counterexample or look for a limiting sentence.
A rejected inference does not have to be false. It may simply remain unproved. This distinction prevents choosing an attractive story when the task asks what follows. Conversely, do not reject a supported choice just because it avoids an interesting broader conclusion.
08 / UNDERSTAND & APPLY
Use the library passage for questions 1–6.
ORIGINAL PRACTICE · 1
No.
A user could collect exactly the same loans at a different time. No individual borrowing totals are provided.
ORIGINAL PRACTICE · 2
A
The explicit “not every” statement entails A. B confuses availability with registration; C is rejected as a guarantee; D is unmeasured; E confuses users with a sample of users.
ORIGINAL PRACTICE · 3
No.
Travel distance was not asked about. Neither scheduling convenience nor branch location supplies distance data.
ORIGINAL PRACTICE · 4
People in the surveyed sample of locker users who responded.
It cannot be expanded to all users, all cardholders or all townspeople without evidence about selection and response.
ORIGINAL PRACTICE · 5
A collected book need not be read, and locker collection may substitute for a daytime visit.
The first blocks collection → reading; the second blocks convenience → additional borrowing. The passage does not claim reading actually fell.
ORIGINAL PRACTICE · 6
No.
The director explicitly accepts a scheduling benefit for at least some existing users and retains the lockers. Rejecting a broader claim is not rejecting the narrower one.
09 / UNDERSTAND & APPLY
A laboratory records: Every sample placed in cabinet R was sealed. Some sealed samples were stored elsewhere. No sample in cabinet R was discarded during the audit.
ORIGINAL PRACTICE · 1
C
The contrapositive of “in R → not discarded” is “discarded → not in R.” A and D conflict with sealed samples elsewhere; B improperly extends the protection to all sealed samples; E conflicts with samples elsewhere.
ORIGINAL PRACTICE · 2
Yes; the statements permit it but do not require it.
Only samples in R are protected by the no-discard statement. The facts give no disposal rule for samples elsewhere. “Could” is a consistency test, not an assertion that disposal occurred.
KEEP THE BIG IDEAS
READ WITH CONTEXT
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