Critical Reasoning

According to a recent study, a diet that is free of meat and diary products greatly reduces the risk of suffering a hear attack. The study cites the fact that only 10% of those who consume such a diet suffer a heart attack at some point in their lives.

Which if the following would most seriously weaken the argument above ?

A) Diets free of meat and diary are low in calcium, which can lead to bone density decreases.

B) Those who consume only diary but not meat are twice as likely to suffer a heart attack as those who consume neither
meat nor diary.

C) Some people who consume neither diary nor meat suffer 2 or more heart attacks over the course of a lifetime.

D) Meat and diary products are high in low-density cholesterol,which is known to harden arteries and cause other heart
problems.

E) 7% of those who consume dairy and meat regularly suffer heart attacks over the course of their lifetime.


Source : Kaplan.

To weaken the argument we have to give a evidence which shows that consuming meat and diary products do not reduce the risk of heart attack (less number of people are affected). Whenever arguments involve percentages, they have to be dealt with possibilities of the number of people surveyed/studied. Here in this case(According to E) if the number of people who consume meat and diary products are less in number as compared to the assumed figure (out of which 10% suffer from heart attack) lets say 100 people do not consume meat and diary;therefore 10 people suffer from heart attack, now lets assume only 10 people consume meat and diary then as per E, 7 people suffer from heart attack, the argument is weakened here, if we now expand the the number of people who consume meat and diary products to 1000, then we have 70 cases of heart attack, the argument gets strengthened now, I considered this possibility while considering option E.

While comparing two sides (a survey to be more specific) do we have to take into account the same number (Number picked for evaluating the survey) ? That is consider the same number of people (say 100) for both groups - people who consume diary and meat and people who do not consume diary and meat.

I face problems dealing with survey arguments (rather percent arguments). Please suggest valuable thoughts on the above problem and also how to deal with percent arguments.

Thanks.

Hello,

How about C?

Since we have to weaken the argument, we have to show that meat and diary free diet doesn't help to reduce the heart attack risk. If some people who are on such diet suffer 2+ heart attacks during their lifetime, it is very reasonable not to be on such diet.

IMO it's D. Pls post OA.

It should be C
A : out of scope
B, D, E : strengthening the argument

My vote goes to : C

I request Experts to please comment on my doubt and the question.

Thanks.

The reasoning you have given comes into play when you are comparing number with percentage. Since we are comparing the % in both the cases, choice E is the best.

beat_gmat_09 wrote:According to a recent study, a diet that is free of meat and diary products greatly reduces the risk of suffering a hear attack. The study cites the fact that only 10% of those who consume such a diet suffer a heart attack at some point in their lives.

Which if the following would most seriously weaken the argument above ?

A) Diets free of meat and diary are low in calcium, which can lead to bone density decreases.

B) Those who consume only diary but not meat are twice as likely to suffer a heart attack as those who consume neither
meat nor diary.

C) Some people who consume neither diary nor meat suffer 2 or more heart attacks over the course of a lifetime.

D) Meat and diary products are high in low-density cholesterol,which is known to harden arteries and cause other heart
problems.

E) 7% of those who consume dairy and meat regularly suffer heart attacks over the course of their lifetime.


Source : Kaplan.

To weaken the argument we have to give a evidence which shows that consuming meat and diary products do not reduce the risk of heart attack (less number of people are affected). Whenever arguments involve percentages, they have to be dealt with possibilities of the number of people surveyed/studied. Here in this case(According to E) if the number of people who consume meat and diary products are less in number as compared to the assumed figure (out of which 10% suffer from heart attack) lets say 100 people do not consume meat and diary;therefore 10 people suffer from heart attack, now lets assume only 10 people consume meat and diary then as per E, 7 people suffer from heart attack, the argument is weakened here, if we now expand the the number of people who consume meat and diary products to 1000, then we have 70 cases of heart attack, the argument gets strengthened now, I considered this possibility while considering option E.

While comparing two sides (a survey to be more specific) do we have to take into account the same number (Number picked for evaluating the survey) ? That is consider the same number of people (say 100) for both groups - people who consume diary and meat and people who do not consume diary and meat.

I face problems dealing with survey arguments (rather percent arguments). Please suggest valuable thoughts on the above problem and also how to deal with percent arguments.

Thanks.

Let me put my opinion here, and please correct me if i'm wrong.

in E: If both the argument and the supporting fact should be in %:

Let's say there are a total of 1000 people. 100 of whom are on a diet. 900 don't follow the diet.
10%=10 people who are on diet suffer from HA.
7%= 63 people who are not on diet suffer from HA.
This strengthens the argument, since the number of people who are not on diet and who suffer from HA can be more that that of who are on diet.

If the number of people who are on diet and who are not is the other way around, then:
10%*900=90
7%*100=7
Many more people who are on diet suffer from HA that those who are not on a diet. This definitely weakens the argument.

I thought no matter what combination we input here, both results should either strengthen or weaken the argument.

Feruza Matyakubova wrote:Let me put my opinion here, and please correct me if i'm wrong.

in E: If both the argument and the supporting fact should be in %:

Let's say there are a total of 1000 people. 100 of whom are on a diet. 900 don't follow the diet.
10%=10 people who are on diet suffer from HA.
7%= 63 people who are not on diet suffer from HA.
This strengthens the argument, since the number of people who are not on diet and who suffer from HA can be more that that of who are on diet.

If the number of people who are on diet and who are not is the other way around, then:
10%*900=90
7%*100=7
Many more people who are on diet suffer from HA that those who are not on a diet. This definitely weakens the argument.

I thought no matter what combination we input here, both results should either strengthen or weaken the argument.

This is what the point i m trying to make, for percents the figures could be anything, how come then we select equal figures and conclude that 7% being less than 10% means that the argument is weakened, moreover we don't even have anything concrete in the stimulus to assume so.

C conveys us that some people suffer HA two or more times, which i think weakens the argument, even though it is some people the fact that they are suffering HA more than once is sufficient to prove that C weakens.

But the Official explaination considers C not to be matching with the statistics and discards this option. Whereas for E there is no explaination given, which i am convinced of, for a comparison of 7% and 10%.

I think it should be considered in this way - > If diet free of meat & dairy products - probability of falling in the grp of ppl with heart desease = 10%

If diet includes meant & dairy products - probability is 7%.

beat_gmat_09 wrote:

Feruza Matyakubova wrote:Let me put my opinion here, and please correct me if i'm wrong.

in E: If both the argument and the supporting fact should be in %:

Let's say there are a total of 1000 people. 100 of whom are on a diet. 900 don't follow the diet.
10%=10 people who are on diet suffer from HA.
7%= 63 people who are not on diet suffer from HA.
This strengthens the argument, since the number of people who are not on diet and who suffer from HA can be more that that of who are on diet.

If the number of people who are on diet and who are not is the other way around, then:
10%*900=90
7%*100=7
Many more people who are on diet suffer from HA that those who are not on a diet. This definitely weakens the argument.

I thought no matter what combination we input here, both results should either strengthen or weaken the argument.

This is what the point i m trying to make, for percents the figures could be anything, how come then we select equal figures and conclude that 7% being less than 10% means that the argument is weakened, moreover we don't even have anything concrete in the stimulus to assume so.

C conveys us that some people suffer HA two or more times, which i think weakens the argument, even though it is some people the fact that they are suffering HA more than once is sufficient to prove that C weakens.

But the Official explaination considers C not to be matching with the statistics and discards this option. Whereas for E there is no explaination given, which i am convinced of, for a comparison of 7% and 10%.