PracticeVerbal
GMAT assumption questions
An assumption is not just a fact that helps. It is a bridge the argument needs. This set makes that distinction visible by explaining what happens when each tempting answer is negated.
If the argument survives the answer being false, the answer was not an assumption — however supportive it sounded. That single test resolves most of the disagreement students have with the official key on these questions.
What this set trains
- The negation test, applied properly: negate minimally, then ask whether the conclusion still follows
- Necessary versus sufficient support — the difference between a bridge and a buttress, covered at Necessary vs. Sufficient
- Scope control, where the answer is true and relevant and about something slightly different from the conclusion
- Causal arguments, where the assumption is usually "no alternative cause" or "not the reverse direction"
- Plans and forecasts, where the assumption is usually that a condition holding today keeps holding
The wrong answers in this set are built deliberately: each is a strengthener, a background fact, a scope shift, or a restatement of the conclusion. Recognising which of the four you picked is more useful than knowing you were wrong.
A national government proposes to lease a protected forest to a logging company, arguing that timber exports will substantially increase national revenue. The forest is currently used by several ecotourism lodges that attract foreign visitors, whose spending supports local communities and generates tax revenue.
Which of the following is an assumption required by the government's argument?
Answer: A
The argument that timber exports will substantially increase national revenue assumes that the new revenue is not offset by lost ecotourism revenue. If the ecotourism revenue lost exceeds the timber gains, the economy would not benefit on net. Therefore A is required. B contradicts the given information and is not necessary. C and D impose a uniqueness or optimality requirement not implied by the argument. E is too weak and not required; even if some ecotourism remains, the net loss must still be outweighed.
Original GMAT-style question written for Premiergrad and checked by an independent blind solve. Not an official GMAT question.
Health Minister: Local officials in provinces controlled by opposition parties claim the recent cuts to community health grants are political retribution. They note that 90 percent of the cut grants went to such provinces. However, every cut grant had been identified by independent auditors as failing to meet health-outcome reporting standards. So the cuts were motivated by compliance standards, not political retribution.
Which of the following is an assumption on which the health minister's argument depends?
Answer: A
The health minister argues that all cut grants failed compliance standards, so the motive was compliance. This requires that the set of grants failing standards was not mostly in the minister's own party provinces; otherwise cutting mostly opposition-province grants would indicate political retribution. Thus A is required. B is irrelevant: other punishment methods do not bear on the motive for these cuts. C concerns overall proportion, not selection bias. D invokes funding levels, which are not part of the minister's justification. E concerns whether opposition officials trust the auditors, not whether the auditors' list supports the inference.
Original GMAT-style question written for Premiergrad and checked by an independent blind solve. Not an official GMAT question.
A hospital's machine-learning system predicts sepsis by continuously monitoring electronic medical record data and matching it to a large database of sepsis cases. In a retrospective review, the system would have identified 95 percent of patients who developed sepsis, on average several hours before clinicians first suspected it. Therefore, if the system is used in the hospital's emergency department, it will reduce the number of deaths from sepsis in that department.
Which of the following is an assumption on which the argument depends?
Answer: E
The conclusion moves from the system's ability to give earlier warning to a reduction in deaths. This requires that earlier warning be acted on in ways that improve survival; if earlier warnings did not change treatment or such treatment did not reduce mortality, the predicted reduction in deaths would not follow. Thus E is necessary. A is not necessary because the system could reduce deaths even if the retrospective review occurred elsewhere, provided the prediction generalizes; the argument does not depend on its being from the same hospital. B is not necessary because the system can be effective even if sepsis is not the most common outcome. C is not necessary because the system could reduce deaths even with a static database. D is an overstatement—past diagnostic failure need not be complete for the system to improve outcomes.
Original GMAT-style question written for Premiergrad and checked by an independent blind solve. Not an official GMAT question.
Archaeologist: In a study of ancient tool-making traditions, only the people of Culture X produced standardized stone blades in a way that left unambiguous evidence of systematic sequence planning. Other contemporaneous cultures did not produce such standardized blades. This indicates that Culture X possessed a capacity for abstract planning unique among contemporaneous cultures.
The archaeologist's argument depends on which of the following assumptions?
Answer: B
The archaeologist concludes that Culture X alone possessed abstract planning because only Culture X produced standardized stone blades with evidence of sequence planning. The argument requires the assumption that producing such blades is necessary for abstract planning: a culture that did not produce them lacked that capacity. Option B states this necessary condition. Option A restates the conclusion. Option C wrongly infers that producing simple flakes precludes abstract planning. Option D presents a false dichotomy between standardized blades and no tools at all. Option E weakens the argument by suggesting abstract planning could exist without standardized blades.
Original GMAT-style question written for Premiergrad and checked by an independent blind solve. Not an official GMAT question.
A city ordinance requires every brick-and-mortar grocery store to donate unsold edible food to food banks, with the goal of reducing both food waste and hunger among city residents. But this ordinance will soon fail to have any meaningful effect: an increasing proportion of food purchases in the city are made through online grocery delivery services, which operate from centralized warehouses and are not classified as brick-and-mortar grocery stores under the ordinance.
Which of the following is an assumption on which the argument depends?
Answer: C
The conclusion that the ordinance will fail to have any meaningful effect depends on the assumption that online grocery delivery will not just add another purchasing channel but will displace brick-and-mortar grocery stores to the point where their donations no longer meaningfully reduce food waste or hunger. If brick-and-mortar stores continue to handle a substantial share of food purchases, their unsold-food donations still reduce waste and hunger. A is irrelevant because the ordinance applies to brick-and-mortar stores, not online services. B is scope creep: the argument need not assume there are no other benefits. D is an unsupported comparison. E is too strong: the ordinance can reduce food waste and hunger even if not every food retailer is covered.
Original GMAT-style question written for Premiergrad and checked by an independent blind solve. Not an official GMAT question.
Your result on the public set
— / 5
5 of 17 questions in this collection are public.
- A raw score out of 5 tells you very little on its own — the useful signal is the shape of the misses, and that is what the notes under each question describe.
- If two or more of your wrong answers were correct work on a different target, that is a pattern rather than a bad day.
Reading your own result
- You keep picking strengtheners. The most common miss, and the most fixable. The answer helped, so it felt right. Run the negation properly and it survives — which is the proof it was not needed.
- You keep picking the widest-sounding option. Assumption answers are often unexciting and narrow. An answer that makes a grand claim usually proves too much to be necessary.
- You keep picking the conclusion restated. You have identified the conclusion correctly, which is not nothing — the gap between premise and conclusion is what is still invisible.
- You are right but slow. That is a different problem, and Timing problem or knowledge problem? is the page for it.
What Lumen looks for
Lumen reads the answer you chose, not just whether it was wrong. On a question like this it separates three things that all look identical in a score: a concept you have not met, a reasoning step that went sideways, and a correct method pointed at the wrong target. Those need three different next weeks, and only the third one is fixed by re-reading the topic.
A single answer is weak evidence and Lumen says so. It becomes a diagnosis when the same shape shows up across several questions — which is the part a page like this cannot do for you.
Related
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Concept
Assumptions
An assumption is an unstated claim the argument requires for its evidence to support its conclusion.
The bridge an argument needs, and how to find it.
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Trap
Necessary vs. Sufficient
A necessary condition must be present for a result to occur. A sufficient condition guarantees the result. The GMAT…
The distinction most misses in this set turn on.
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Concept
Causal Reasoning
A causal argument says that changing or observing X explains a change in Y. The GMAT tests whether the evidence…
Where the assumption is "no alternative cause".
Continue the full set
The questions above are the public part of this collection. An account adds the rest of the set, your attempts saved, and a diagnosis of the answer you actually chose rather than a general explanation.
Continue with the full set Everything on this page stays free and open — no account needed to read it or to attempt the questions above.