Critical Reasoning

In 1998, more citizens from the country of Monrovia migrated from Monrovia to neighboring Abstania than during any prior year. In 1998, the number of reported violent crimes in Abstania increased dramatically over 1997. The unavoidable conclusion is that Monrovians who migrated from Monrovia to Abstania were responsible for this increase.

Which of the following statements, if true, would most seriously weaken the claim that Monrovians were responsible for the increase in violent crime in Abstania during 1998?

(A) Each year more violent criminals are apprehended in Abstania than in Monrovia.
(B) During 1998 more violent crimes were reported in Abstania than in Monrovia.
(C) In 1998 no Monrovians migrated from either Monrovia or Abstania to any country other than Monrovia or Abstania.
(D) In 1998 the number of unreported violent crimes in Abstania increased as well.
(E) In 1998 fewer Monrovians migrated from Monrovia to Abstania than from Abstania to Monrovia.


OA E

According to me the answer should have been A

Premise 1: In 1998, more citizens from the country of Monrovia migrated from Monrovia to neighboring Abstania than during any prior year.

Premise 2: In 1998, the number of reported violent crimes in Abstania increased dramatically over 1997.

Conclusion: Monrovians who migrated from Monrovia to Abstania were responsible for this increase.

Two potential issues I see here. First, there is a correlation between the number of migrants and the number of reported crimes, but that does not guarantee causation. There might be a third factor that explains both events. Second, the statistic quoted is an absolute number of crimes, which does not account for changes in population.

A--irrelevant. Monrovians could still be committing additional crimes that would increase the overall number reported.

B--irrelevant. We are only concerned with the situation in Abstania.

C--other countries are not part of the argument.

D--the argument is about reported crimes.

E--this one is good. Overall, you have a net loss of Monrovians in Abstania (because the number leaving was greater than the number entering), so it would be hard to argue that they caused an increase in the number of violent crimes reported.

Thanks Bill.I have to add that Veritas does have excellent tips and strategies so far from what Ive read in CR.Success on Weaken questions has reached to 60%,thanks to Veritas.Can you please clarify this doubt that I have.

What if there's a CR Weaken question,and in the answer choice we have an answer that is Anti-Premise.Could that answer be correct?So far those answers have been wrong.The Veritas book clearly states that if you have a repackaged premise in the Weaken answer choices,its a wrong answer.What if I have an anti-premise?Something that just takes down the premise thats used to make a conclusion.Some materials say that anything that brings down an argument in Weaken questions is a wrong one,a GMAT trick.Hence the confusion,please clarify Bill.

Also if I may add,can you please give me a tip list on CR weaken questions(similar to some Ive mentioned above,such as cautions,GMAT tricks etc) so that I could print it out and keep it for easy mobile reference?For example -Tips like those mentioned in that book.

Thanks Bill

Bill@VeritasPrep wrote:Premise 1: In 1998, more citizens from the country of Monrovia migrated from Monrovia to neighboring Abstania than during any prior year.

Premise 2: In 1998, the number of reported violent crimes in Abstania increased dramatically over 1997.

Conclusion: Monrovians who migrated from Monrovia to Abstania were responsible for this increase.

Two potential issues I see here. First, there is a correlation between the number of migrants and the number of reported crimes, but that does not guarantee causation. There might be a third factor that explains both events. Second, the statistic quoted is an absolute number of crimes, which does not account for changes in population.

A--irrelevant. Monrovians could still be committing additional crimes that would increase the overall number reported.

B--irrelevant. We are only concerned with the situation in Abstania.

C--other countries are not part of the argument.

D--the argument is about reported crimes.

E--this one is good. Overall, you have a net loss of Monrovians in Abstania (because the number leaving was greater than the number entering), so it would be hard to argue that they caused an increase in the number of violent crimes reported.

(E) In 1998 fewer Monrovians migrated from Monrovia to Abstania than from Abstania to Monrovia.

The people who leave from Abstania to Monrovia,are they Monrovians?They could be Abstanians too right?

Lets assume 200 Monrovians enter Abstania,and 300 Abstanians leave Monrovia.How can this weaken the argument?

Bill@VeritasPrep wrote:Premise 1: In 1998, more citizens from the country of Monrovia migrated from Monrovia to neighboring Abstania than during any prior year.

Premise 2: In 1998, the number of reported violent crimes in Abstania increased dramatically over 1997.

Conclusion: Monrovians who migrated from Monrovia to Abstania were responsible for this increase.

Two potential issues I see here. First, there is a correlation between the number of migrants and the number of reported crimes, but that does not guarantee causation. There might be a third factor that explains both events. Second, the statistic quoted is an absolute number of crimes, which does not account for changes in population.

A--irrelevant. Monrovians could still be committing additional crimes that would increase the overall number reported.

B--irrelevant. We are only concerned with the situation in Abstania.

C--other countries are not part of the argument.

D--the argument is about reported crimes.

E--this one is good. Overall, you have a net loss of Monrovians in Abstania (because the number leaving was greater than the number entering), so it would be hard to argue that they caused an increase in the number of violent crimes reported.

dddanny2006 wrote:In 1998, more citizens from the country of Monrovia migrated from Monrovia to neighboring Abstania than during any prior year. In 1998, the number of reported violent crimes in Abstania increased dramatically over 1997. The unavoidable conclusion is that Monrovians who migrated from Monrovia to Abstania were responsible for this increase.

1998 - Migration from City " M " ----- > City " A " highest , compared to previous years.

1998 - Violent crimes in City " A " increased dramatically over Previous year.

Conclusion - People who migrated to City " A " from City " M " are responsible for it. ( Hence most people who migrated to city " M " were criminals )

Which of the following statements, if true, would most seriously weaken the claim that Monrovians were responsible for the increase in violent crime in Abstania during 1998?

(A) Each year more violent criminals are apprehended in Abstania than in Monrovia.

The passage talks about a spurt in Crime cases over its previous year in City " A " and this options is no way relevant to the present discussion and our objective of weakening the Conclusion arrived at int he passage presented to us.

(B) During 1998 more violent crimes were reported in Abstania than in Monrovia.

Irrelevant

(C) In 1998 no Monrovians migrated from either Monrovia or Abstania to any country other than Monrovia or Abstania.

Thus the movement of People is as follows -

City A --------- > City M

City M ----------> City A

This is no way related to weakening the conclusion arrived at in the passage.

(D) In 1998 the number of unreported violent crimes in Abstania increased as well.

We know it , nothing new ..

(E) In 1998 fewer Monrovians migrated from Monrovia to Abstania than from Abstania to Monrovia.

Migration from City M to A < Migration from city A to City M

Hence the sudden spurt in crime rates in city A is not due to influx of Criminals from city M to A but City A nurtured those criminals them self.

Hence Imo (E)

dddanny2006 wrote:
What if there's a CR Weaken question,and in the answer choice we have an answer that is Anti-Premise.Could that answer be correct?So far those answers have been wrong.The Veritas book clearly states that if you have a repackaged premise in the Weaken answer choices,its a wrong answer.What if I have an anti-premise?Something that just takes down the premise thats used to make a conclusion.Some materials say that anything that brings down an argument in Weaken questions is a wrong one,a GMAT trick.Hence the confusion,please clarify Bill.

If by Anti-Premise, you mean a new piece of evidence that contradicts evidence given in the stimulus, then no. Premises given in the stimulus are true: if the stimulus tells you that "all widgets are red" and an answer choice says "there are widgets that are not red", it is a trap answer.

By repackaged premise, we mean an answer choice that gives you the exact same information, just in a different form. If the stimulus says "all widgets are red", and an answer choice says that "scientific research has shown that it is impossible for a widget to be anything but red", it doesn't do anything to the argument because you already knew it.

Also if I may add,can you please give me a tip list on CR weaken questions(similar to some Ive mentioned above,such as cautions,GMAT tricks etc) so that I could print it out and keep it for easy mobile reference?For example -Tips like those mentioned in that book.

Here are a few things that I do on Weaken questions:

1. After the stimulus, consider why I don't believe the argument--why is it not convincing? what's missing? what's questionable?

2. Look for an alternative explanation--if the argument is that "A causes B", one of the most direct ways to weaken is to show that it's actually C that causes B.

3. Be skeptical of statistics--if data is used, make sure it's the correct type (actual number vs. rate/proportion) and make sure the wording of the stat fits the wording of the conclusion.

4. Pay attention to scope--the answer must give us something new, but it has to relate to what was already given.

dddanny2006 wrote:(E) In 1998 fewer Monrovians migrated from Monrovia to Abstania than from Abstania to Monrovia.

The people who leave from Abstania to Monrovia,are they Monrovians?They could be Abstanians too right?

Lets assume 200 Monrovians enter Abstania,and 300 Abstanians leave Monrovia.How can this weaken the argument?

Let's use some SC knowledge to break this down

(E) In 1998 fewer Monrovians migrated from Monrovia to Abstania than from Abstania to Monrovia.

We are only talking about Monrovians moving between the two countries. Any migration of Abstanians is not mentioned.