Of 2,500 people who survived a first heart attack, those who did not

Question

Of 2,500 people who survived a first heart attack, those who did not smoke had their first heart attack at a median age of 62. However, of those 2,500, people who smoked two packs of cigarettes a day had their first heart attack at a median age of 51. On the basis of this information, it can be concluded that nonsmokers tend to have a first heart attack eleven years later than do people who smoke two packs of cigarettes a day.

The conclusion is incorrectly drawn from the information given because this information does not include

(A) the relative severity of heart attacks suffered by smokers and nonsmokers

(B) the nature of the different medical treatments that smokers and nonsmokers received after they had survived their first heart attack

(C) how many of the 2,500 people studied suffered a second heart attack

(D) the earliest age at which a person who smoked two packs a day had his or her first heart attack

(E) data on people who did not survive a first heart attack

noboru · Answer

Imagine this situation:

Ages of people who smoke >2 packets: 50 50 50 50 50 50 50....50  51  62 62 62 62 62 ....62
Ages of people who dont smoke: 50 50 50 50 50 50 50 ...50  62  62 62 62 62 62 ....62

Median of first groups: 51
Median of second groups: 62

Both groups tend to have a first heart attack not eleven years later than do people who smoke two packs of cigarettes a day, but at the same age, therefore the conclusion is incorrectly drawn.

For this reason, Im with D.

ykaiim · Answer

It's a twisted FLAW in reasoning question. Good one.

IMO E.
If we dont know how many smokers/non-smokers survived their first encounter then it will be difficult to conclude. What if majority of NS die on first HA before the 51?

Argument states info only on first HA survivers but not on non-survivers. So, I go with my intuition here. This point is what E catches.

analyst218 · Answer

the argument has nothing to do with Non survivors. 
it incorrectly generalizes about all non smokers and smokers because it assumes that all non smokers experienced HA at the same age from a median data. 
Median does not tell you the age at which all smokers experience HA. Median is a median.

So as in D, one of the smokers might have experienced HA at the age of 10 and others at the median age. and the median would still be unchanged. Would the argument still be valid? No.

bibha · Answer

IMO it is "E"....The argument begins with a specific sample "of those who survived their first HA....." then in the end it generalizes to "all the non smokers and smokers" 
 What is the OA?

govindsowrirajan · Answer

IMHO, E

A:Severity of heart attack is out of scope
B:Medical treatment is out of scope
C:2nd heart attack is out of scope
D: Knowing the earliest age does not help in any way to determine anything when we are considering medians.
E:The conclusion compares smokers and non smokers in general whether they survived or not but the data in hand says nothing about those who died of their first heart attack. Such a conclusion cannot be made from that so this is  Correct

Initially, I also thought that it would be D because it is the only choice which speaks about the age of the persons involved.

amolg · Answer

(A) the relative severity of heart attacks suffered by smokers and nonsmokers Severity doesnt matter, the comaprison is about the first heart attack (B) the nature of the different medical treatments that smokers and nonsmokers received after they had survived their first heart attack What happens after the heart attach doesnt matter, for this argument

(C) how many of the 2,500 people studied suffered a second heart attack Second heart attack is out of question (D) the earliest age at which a person who smoked two packs a day had his or her first heart attack Correct . The conclusion is, difference of 11 years to have first heart attack between non-smokers and smokers. This conclusion is invalid if majority of this median is before or after 51 years. So 11 years difference is wrong indicator. (E) data on people who did not survive a first heart attack What happens after the heart attack is irrelevent for the conclusion, read the conclusion carefully.

francoimps · Answer

First of all, the OA is E. This is an Official LSAT Question (Test #10 of "10 Actual Tests").

Of 2,500 people who   survived   a first heart attack, those who did not smoke had their first heart attack at a median age of 62. However, of those 2,500, people who smoked two packs of cigarettes a day had their first heart attack at a median age of 51. On the basis of this information, it can be concluded that  nonsmokers    tend   to have a first heart attack eleven years later than do people  who smoke  two packs of cigarettes a day.
The conclusion is incorrectly drawn from the information given because this information does not include
(A) the relative severity of heart attacks suffered by smokers and nonsmokers
(B) the nature of the different medical treatments that smokers and nonsmokers received after they had survived their first heart attack
(C) how many of the 2,500 people studied suffered a second heart attack
(D) the earliest age at which a person who smoked two packs a day had his or her first heart attack
(E) data on people who did not survive a first heart attack

Note that the argument focuses its premises on people who  survived  their first heart attack. The argument however makes a broader statement in its conclusion: "people who smoke" (note that the "survivor" qualifier is now gone). What if significantly more smokers had their first heart attack at, say, 10 years old, but they ALL DIED? Therefore, the conclusion that nonsmokers tend to have a first heart attack 11 years later than do people who smoke is INVALID. You see, by broadening its conclusion, it had made an unwarranted generalisation.

And yes you are correct, read the conclusion carefully.

JLAR2107 · Answer

By mapping the argument we see that of those that  survived  their first heart attack, the median age at which a person suffered a heart attack was lower for those that smoked. We need to try to find a reason this conclusion was incorrectly drawn.

(A) the relative severity of heart attacks suffered by smokers and nonsmokers
The severity of the heart attack really has nothing to do with the median age at which a person first suffers from a heart attack. Therefore this does not really affect the conclusion.

(B) the nature of the different medical treatments that smokers and nonsmokers received after they had survived their first heart attack
The medical treatment  after  a heart attack does not affect the median age at which a person will first suffer a heart attack.

(C) how many of the 2,500 people studied suffered a second heart attack
This is not relevant to the difference in median age at which a person first suffers a heart attack.

(D) the earliest age at which a person who smoked two packs a day had his or her first heart attack
There could be outliers that lead to inconclusive data. For example someone with a genetic condition could have a heart attack at an age earlier than 51 whether or not they smoked.

(E) data on people who did not survive a first heart attack
This sample population could potentially affect the difference in the median age at which smokers vs. non-smokers get their first heart attack

---> The correct answer is  E

dharam44 · Answer

please explain why E is the correct answer?

GMATNinja   egmat

auradediligodo · Answer

Of 2,500 people who survived a first heart attack, those who did not smoke had their first heart attack at a median age of 62. However, of those 2,500, people who smoked two packs of cigarettes a day had their first heart attack at a median age of 51. On the basis of this information, it can be concluded that nonsmokers tend to have a first heart attack eleven years later than do people who smoke two packs of cigarettes a day.

The conclusion is incorrectly drawn from the information given because this information does not include

Identify the flaw question

Pre-thinking

The information used to draw the conclusion is from people who survived an heart attack while the conclusion is about both people who survived and people who did not survive.
  Flaw#1  : data from people who survived an heart attack is insufficient, we need also the data from those who did not survive.
  Flaw#2  : the data used to draw the conclusion is about the median while the conclusion is a general statement. It would be more correct to use averages in both the premises and the conclusion

(A) the relative severity of heart attacks suffered by smokers and nonsmokers
 irrelevant

(B) the nature of the different medical treatments that smokers and nonsmokers received after they had survived their first heart attack
 irrelevant

(C) how many of the 2,500 people studied suffered a second heart attack
 irrelevant

(D) the earliest age at which a person who smoked two packs a day had his or her first heart attack
 irrelevant

(E)   data on people who did not survive a first heart attack
 In line with our pre-thought flaw #1

dharam44 · Answer

Would you please explain your logic with example. 
 auradediligodo

auradediligodo · Answer

I hope this example will clarify any doubts.

Let's assume that 10000 people died after the first heart attack and 2500 survived as the argument claims. Now we are given data related only to the 2500 people who survived while the conclusion includes also the 10000 people who didi not survive. 
Now let's imagine that the trend was reversed for those 10000 people: the non smokers died at 51 (median) and the smokers at 62(median). From this data the conclusion drawn from the argument is not valid.
Hence the flaw consists in not taking into account the people who died from heart attack#1

dharam44 · Answer

thanks a lot for response

%20%20%20%20 auradediligodo

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Of 2,500 people who survived a first heart attack, those who did not

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