All practice questions

In Logical Reasoning, the Negation Technique is used to test whether an assumption is truly necessary for an argument to hold. This technique requires accurately forming the logical negation of a candidate assumption statement. Match each assumption statement below with its exact logical negation.

City Planner: In order to significantly reduce the severe traffic congestion in our downtown commercial district, the municipal government should construct a new high-capacity bypass highway on the western outskirts of the city. Recent engineering studies demonstrate that this proposed bypass highway is designed to handle up to 20,000 vehicles per day. This capacity perfectly matches the estimated volume of excess commuter traffic that is currently clogging the main downtown routes during peak hours.

Statement: To properly evaluate the city planner's argument, it is necessary to determine whether the commuters currently traveling through the downtown district would actually choose to alter their routes to use the new western bypass highway.

Under current legal frameworks, a decentralized autonomous organization (DAO) can be held legally liable for damages only if it features either a central executive committee or a pre-coded compensation fund. The Aetherium Network is a DAO that was recently held legally liable for damages by a federal court. However, an exhaustive audit of the network's architecture proves that it lacks any pre-coded compensation fund. Therefore, it is clear that the Aetherium Network must utilize a weighted-voting governance protocol.

Which one of the following, if assumed, enables the conclusion to be properly drawn?

City official: The newly constructed eastern bypass road will significantly reduce the severe traffic congestion currently experienced on Main Street. This is because the bypass will finally provide a more direct, faster route for heavy commercial trucks traveling between the industrial park and the interstate highway, meaning these vehicles will no longer need to drive through the city center.

The city official's argument relies on the assumption that commercial trucks currently contribute to the traffic congestion on Main Street.

Environmental Advocate: The proposed multinational treaty to permit deep-sea mining should be rejected immediately. Dr. Aris Thorne, the world’s preeminent marine biologist and leading authority on abyssal plain ecosystems, recently testified that the short-term revenue generated by deep-sea mining will inevitably be overshadowed by the long-term financial collapse of global fisheries. Since no single individual possesses a deeper understanding of the ocean's intricate ecosystems than Dr. Thorne, we must accept his conclusion that deep-sea mining is a disastrous economic strategy.

Which of the following most accurately describes a flaw in the environmental advocate's reasoning?

Botanist: Ghost orchid seeds require a specific soil fungus to germinate. In Silverwood Forest, this fungus is found exclusively in the decomposing bark of fallen elder-pine trees. Therefore, the new forest management policy, which mandates the removal of all fallen elder-pine trees from Silverwood to reduce wildfire risk, will inevitably cause the forest's ghost orchid population to decline.

Which one of the following is an assumption on which the botanist's argument depends?

The new administrative software update reduces the time it takes for employees to process customer requests by 20 percent. Therefore, the company should mandate that all employees install the new software update immediately.

Which one of the following principles, if valid, most helps to justify the reasoning above?

University Administrator: Ten years ago, 15 percent of the enrolled students at our university were majoring in the humanities. This year, only 10 percent of our enrolled students are majoring in the humanities. Therefore, the actual number of humanities majors on campus today must be lower than it was ten years ago.

Which one of the following most accurately describes the flaw in the administrator's reasoning?

Match each argument (stimulus) with the supporter assumption that is necessary to bridge the logical gap between its premise and its conclusion.

The university has announced that any student who completes the advanced research seminar will be awarded a special graduation commendation. Therefore, we can be certain that every student majoring in history will be awarded this special graduation commendation.

Which one of the following, if assumed, enables the argument's conclusion to be properly drawn?

A linguist is arguing that a newly discovered dialect should be classified as a distinct language. The linguist's initial premise is that 'the new dialect shifts the core phonetic boundaries of the original language.' The final conclusion is that 'the new dialect must be classified as a distinct language.'

To make this argument logically valid, a series of sufficient assumptions must be added to form a complete deductive chain. Arrange the following assumptions in the correct logical sequence so that each statement's sufficient condition is established by the necessary condition of the previous step (or the initial premise), ultimately guaranteeing the final conclusion.

Read the following argument and evaluate the subsequent statement.

Historian: During the 1880s, the National Telegraph Company's adoption of the duplex telegraph system—which permitted simultaneous bidirectional transmission—coincided with a 30 percent reduction in garbled dispatches. Clearly, the continuous electrical current required by the duplex system actively suppressed the ambient magnetic interference that typically causes signal degradation.

Statement: A necessary assumption of the historian's argument is that the installation of the duplex telegraph system did not simultaneously require replacing the company's existing unshielded wires with heavily insulated cables.

Analyze each of the following logical arguments. Match each argument to the specific sufficient assumption that, if added to its premises, strictly and logically guarantees the truth of its main conclusion.

Industry Analyst: The widespread adoption of remote work over the last three years has caused a significant drop in the sales and profitability of formal business attire. Consequently, the recent decline in the overall profit margins of the retail clothing sector is a direct result of this transition to remote work.

For the analyst's conclusion to be properly drawn, it is necessary to assume that the transition to remote work did not generate a surge in casual clothing profits that completely offset the losses from formal business attire.

Consider the following argument:

'An independent consumer advocacy group sought to determine the reliability of the newly released Zephyr X-series washing machines. They mailed satisfaction questionnaires to 10,000 people who had purchased a Zephyr X-series machine within the last six months. Of the 1,500 people who returned the questionnaire, nearly 90 percent reported experiencing at least one major mechanical failure. Based on this data, the group concluded that the Zephyr X-series is highly unreliable.'

The primary logical flaw in this argument is that it draws a broad conclusion from a sample size (1,500 respondents) that is statistically too small to represent the experiences of all purchasers.

A manufacturer of various athletic equipment recently released a premium line of smart treadmills. To assess overall customer satisfaction with the manufacturer's entire range of products, the company emailed a survey exclusively to customers who had registered the new smart treadmills for warranty purposes. Over 95 percent of the respondents reported being extremely satisfied with their purchase. Based on this, the company's executive team concluded that nearly all of their customers are highly satisfied with the brand.

The reasoning in the executive team's argument is most vulnerable to criticism on the grounds that it

Literary Critic: In her latest novel, every individual chapter ends with a definitive resolution to the conflicts introduced within that specific chapter. Therefore, the novel as a whole must provide readers with a definitive resolution to its overarching narrative.

Which one of the following arguments contains a flawed pattern of reasoning most similar to the one exhibited by the literary critic's argument?

In Logical Reasoning, a 'Defender Assumption' is a necessary assumption that protects a causal conclusion by ruling out a specific alternative explanation or vulnerability. Match each causal argument and its corresponding objection (Left) to the precise defender assumption (Right) that the argument MUST make to survive the objection.

Match each argumentative scenario with the universal principle that most helps to logically justify its conclusion.

Whenever a restaurant fails to maintain strict hygiene standards, it receives negative reviews from local food critics. The new seafood diner in town has consistently failed to maintain strict hygiene standards. Therefore, the new seafood diner will be forced to close down within the year.

The conclusion drawn above follows logically if which one of the following is assumed?