During the American westward expansion, a certain city in the eastern

From the problem: "it can be concluded that it was not much more perilous..."

When comparing the peril of staying in an eastern city vs departing westward, the absolute numbers of deaths in each case don't matter, nor do the causes of death (answer C concerns causes of death). For example, it's fallacious to separate out murders and accidents and whatnot, because those may or may not occur at a higher rate in the city.

What matters is the relative number of deaths, no matter the cause, also known as the death rate. It is (# of deaths) divided by (# of people matching the criteria in question). Put simply, answer choice D.

Thanks.
I wonder if this reasoning will be easier for me to understand with more practice.

Thanks.
I should pay more attention to words and go to the extremes.
Thinking like you, 225 out of the whole eastern population.

very good explanation. thanks vercules

very good explanation. thanks vercules

The flaw here is the fact that argument compares all 250 people left east then died to the population of all eastern cities whereas the population can be 100 000 people and only 225 among them died.

KAPLAN OFFICIAL EXPLANATION

Identify the Question Type:

This question is a Flaw question. It asks for the answer choice that would most clearly reveal the logical flaw in the conclusion.

Untangle the Stimulus:

The author concludes there was no increased risk in being a settler versus staying in the east.

As evidence, the author states that during the westward expansion, 250 people who left the east to settle in the west died before arriving at their destination; during the same period 225 people who choose to remain in the east also died.

In order for these statistics to be meaningful, the author must be assuming that the total number of people who stayed in the east was equivalent to the total number of people who went west to settle.

Predict the Answer:

The correct answer choice will reveal something that is not comparable between these two groups. For instance, it might show that the number of people who stayed in the east was far greater than the number of people who attempted to settle in the west.

Eliminate the Wrong Answer Choices:

(D) matches the prediction; knowing the percentage of people in each group who died would much more clearly reveal the flaw in the argument than knowing the absolute number of deaths in each group.

(A) is incorrect because the argument is only concerned with people who died in transit from east to west as compared to those who stayed in the city. Furthermore, the right answer needs to compare those who left to those who stayed, and (A) doesn't give any information about people who stayed.

(B) is an irrelevant comparison; the right answer needs to compare the groups to each other

The cause of death is irrelevant the argument, which is about the number of deaths, so (C) and (E) are incorrect.

TAKEAWAY: This is a classic “numbers vs. percentage” flaw, a type that appears often in flawed GMAT arguments.

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