GMAT Critical Reasoning (CR)

Free online live class on Sep 1, 2017

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Welcome to the live session of GMAT Critical Reasoning (CR) - Weaken an argument. To watch the concepts and questions discussed on September 1, 2017 during the live session follow the embedded video. The video link next to each question will take you to the detailed video explanation for that question. Click the video embedded below to watch the entire session.

GMAT CR Weaken questions discussed on Friday, Sep 1, 2017

  1. The number of townhouses that are being built in the city has significantly increased over the last five years. However, during the same time the total number of housing units sold in the city has decreased by approximately 10% year on year. Therefore, real estate developers must focus on building more apartments and reduce the number of townhouses because the people in our city clearly do not prefer townhouses.

    Which of the following, if true, points out that the conclusion is based on a wrong reasoning?

    1. The cost of a townhouse is approximately three times that of an apartment.
    2. Most of the new townhouses have been built after demolishing older houses that used to stand on that plot.
    3. The population in the city has increased by around 10%, mainly because of an influx of people who are seeking employment.
    4. A poll conducted in the city showed a declining preference for repurchase of houses and apartments.
    5. The average income of the population in the city has increased exponentially, making luxuries more affordable.
  2. It has long been established that teenagers who binge drink are more likely to have alcohol problems in adulthood as well. It was believed that the problem was primarily behavioral or societal – that these teenagers never learnt to cope with stress. However, a study shows that binge drinking as adolescents can lead to gene regulation and disrupt brain development in a manner that promotes anxiety. Thus, it would seem that people do not turn to alcohol to relieve anxiety but rather that turning to alcohol induces anxiety.

    Which of the following, if true, undermines the author’s reasoning?

    1. Gene regulation is a more difficult root cause to control or change than either behavioral or societal causes.
    2. Anxiety is usually not the reason for alcohol abuse but rather an excuse.
    3. Respondents to another study claimed that they had an alcoholic drink at the end of their work day only on days that proved to be especially stressful.
    4. Brain development is not affected for people who take up binge drinking only after reaching adulthood.
    5. All adolescents do not claim anxiety as the reason they resort to binge drinking.
  3. In the town of Shelby, every single building has met the safety stipulations of the fire department and placed adequate fire extinguishers in strategic places throughout the buildings. Also, following a major fire tragedy two years ago, the citizens have learnt the importance of being prepared and many of them have attended the emergency fire drill and lessons offered by the department. The town is no longer exclusively dependant on the fire department and there is no longer a need for the extensive facilities at the department. The mayor’s office can significantly bring down the costs to the government by reducing both the number of trucks and firemen and use the money saved to better implement other schemes.

    Which of the following, if true, best explains why the mayor’s office may not be able to implement the recommendation?

    1. The mayor’s office is not short of funds and has enough money to implement any development project it chooses, without having to reduce the budget of any single department.
    2. The neighboring town of Skywalk has a larger pool of citizens trained in fire fighting but still chooses to maintain a large fire department.
    3. About 10% of the calls that the fire department receives are not related to fire emergencies at all but for other kinds such as pet rescue. 
    4. The reaction time for amateur firefighters is about 45 seconds slower on average than for trained professionals. 
    5. Tackling forest fires is an important responsibility of the town’s fire department, considering the town is located on the edges of a huge national park.
  4. A study was done among a group of prisoners, most of whom had been imprisoned for theft, and among a group of 10-year olds. All the respondents from the two groups had to answer a questionnaire that tested their ethical and moral value systems. It was surprisingly found that most of the prisoners had as strong a sense of right and wrong as the children. Clearly, people are driven to thieving out of necessity and the penalty for such crimes must be reduced from imprisonment to community service.

    Which of the following, if true, LEAST questions the underlying assumptions in the argument?

    1. Imprisonment has been proven to provide time and the environment for reflection and a better understanding of what is right and wrong.
    2. Community service has often proved to be less effective in rectifying criminals than capital punishment.
    3. Often in our culture, kids begin to learn to differentiate between right and wrong only in their early teens.
    4. Many of the kids who responded to the study had a warped sense of right and wrong, influenced by some of the movies they watch.
    5. Answers provided to questionnaires by prisoners often do not present what they think but what they believe people want to hear.
  5. There has long been a debate about whether the extinction of dinosaurs was triggered by a meteor collision or a volcanic eruption. In recent years, evidence has been increasingly found in support of the meteor collision theory, including the identification of a large crater that has been dated toward the end of the cretaceous era and the identification of high iridium levels in clay and marine strata. The high levels of iridium can be explained only by extra-terrestrial influence. However, this does not necessarily resolve the debate because ________

    1. There could have been volcanic eruptions during the same period as well.
    2. The reason for the extinction of the dinosaurs need not be meteors or volcanoes.
    3. The fossils of all the non-avian dinosaurs that have been found pre-date the estimated time of the meteor collision by at least a century.
    4. The meteor collision is thought to have made the earth uninhabitable because the particles in the atmosphere blocked solar radiation and affected oxygen levels and photosynthesis.
    5. There are theories that some of the meteors could have landed in the oceans, not leaving any visible identifiable craters on the earth.
  6. Over the last three years, there has been a measurable shift in the leisure reading preferences of high school students. The most commonly sold or lent out books have dealt with supernatural creatures such as vampires and werewolves. Three years ago, the movie Bites of Death that revolved around both vampires and werewolves was released nationwide and overnight became the biggest blockbuster of the decade. Clearly, three years later, the movie is still influencing the reading preferences of youngsters.

    Which of the following, if true, undermines the author’s reasoning?

    1. Publishing houses in the country spend three times as much promoting supernatural books than any other single genre.
    2. Books on supernatural creatures are also increasingly popular among adult readers.
    3. The school boards in most states in the country do not recommend supernatural books to school students.
    4. Most of the books since have dealt with vampires or werewolves but very rarely both.
    5. There have been other movies that have since been made about vampires and werewolves.
  7. Pet owners need to be careful about diseases that can spread from the pets, especially to children and pregnant women. While there are medications that are frequently recommended by vets to get rid of dangerous bacteria in the urine and feces of dogs and cats, regular bathing of the animals is the only way to ensure that their fur is clean of ticks, along with not letting their pets interact with strays, ensuring that infected fleas and ticks do not spread.

    Which of the following, if true, undermines the author’s reasoning?

    1. Most of the fleas that spread from strays to home pets are not infected.
    2. The bacteria that spread through urine is more dangerous than the ones that spread through fleas.
    3. Regular bathing of pets can still lead to the spread of infected fleas.
    4. A medicated food that the pets can eat creates a pungent smell on their fur that repels fleas.
    5. Bathing too often can lead to fur loss for some species of dogs.

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