# Can anyone explain this flaw question?

#### peace be with you

##### Can anyone explain this flaw question?
« on: January 14, 2010, 04:45:46 PM »
The question that I do not fully understand is prep 33,Section 1, Question 24.

Basically the stimulus says that
the next budget proposal will probably be approved. The reasoning behind is usually about half of all budget proposals that are considered are approved, and the last five budget proposals have all been turned down.

By POE, I got the question right. However, I do not quite fully understand the answer.
The answer says that the fact that the last five budget proposals turned down affects the probablity of the next budget proposal will be turned down...

My question here is that doesn't the last part in the answer have to be "will be approved?" Or is it kind of the same way of putting it in this case because likely of turning down will be the same as being approved??

#### llsatt1

##### Re: Can anyone explain this flaw question?
« Reply #1 on: January 15, 2010, 12:19:59 AM »
The question that I do not fully understand is prep 33,Section 1, Question 24.

Basically the stimulus says that
the next budget proposal will probably be approved. The reasoning behind is usually about half of all budget proposals that are considered are approved, and the last five budget proposals have all been turned down.

By POE, I got the question right. However, I do not quite fully understand the answer.
The answer says that the fact that the last five budget proposals turned down affects the probablity of the next budget proposal will be turned down...

My question here is that doesn't the last part in the answer have to be "will be approved?" Or is it kind of the same way of putting it in this case because likely of turning down will be the same as being approved??

The answer choice doesn't need to say "will be approved" because it's talking about the likelihood that the next budget proposal will be turned down.  This probability can be zero, in which case the next proposal will be approved, or it could be as much as 100 in which case the next proposal will not be approved. Hence, stating the "likelihood that the next budget proposal will be turned down" is the same as saying "...will be approved".  The answer choice is simply stating that the last five budget proposals being turned down does not have any effect on what will happen next.  This is mainly due to the fact that we don't know the total number of budget proposals.

#### peace be with you

##### Re: Can anyone explain this flaw question?
« Reply #2 on: January 15, 2010, 09:22:36 AM »

Thank You! llsatt1!!

#### Changed Name

• 719
##### Re: Can anyone explain this flaw question?
« Reply #3 on: January 15, 2010, 09:51:54 AM »
Just to point out quickly, the real point of the question isn't really the way they phrase the answer.  It speaks to having a basic understanding of probability.  If you have a certain probability of an independent event, then subsequent events are not affected by the previous one.

For example, the probability of getting heads when flipping a coin is 50%.  Thus, just because you have gotten five tails in a row, it doesn't mean that the probability of getting tails on the sixth try is any less (it still remains 50%).

I really think the question is rewarding this type of understanding -- not so much in the way they phrase it (although, that certainly is a part of it).

#### llsatt1

##### Re: Can anyone explain this flaw question?
« Reply #4 on: January 15, 2010, 12:24:17 PM »
Just to point out quickly, the real point of the question isn't really the way they phrase the answer.  It speaks to having a basic understanding of probability.  If you have a certain probability of an independent event, then subsequent events are not affected by the previous one.

For example, the probability of getting heads when flipping a coin is 50%.  Thus, just because you have gotten five tails in a row, it doesn't mean that the probability of getting tails on the sixth try is any less (it still remains 50%).

I really think the question is rewarding this type of understanding -- not so much in the way they phrase it (although, that certainly is a part of it).

what you say is true, but it doesn't apply to this particular question.  flipping a coin is always an independent event, so it doesn't matter what happens before it.  In the case of this LSAT question, since about half are approved, knowing how many have not been approved could make a difference, but only if you know the total amount that are being considered in the first place.

#### Changed Name

• 719
##### Re: Can anyone explain this flaw question?
« Reply #5 on: January 16, 2010, 04:58:42 PM »
Just to point out quickly, the real point of the question isn't really the way they phrase the answer.  It speaks to having a basic understanding of probability.  If you have a certain probability of an independent event, then subsequent events are not affected by the previous one.

For example, the probability of getting heads when flipping a coin is 50%.  Thus, just because you have gotten five tails in a row, it doesn't mean that the probability of getting tails on the sixth try is any less (it still remains 50%).

I really think the question is rewarding this type of understanding -- not so much in the way they phrase it (although, that certainly is a part of it).

Oh good point.  I totally didn't catch that when reading the description of the stem.

what you say is true, but it doesn't apply to this particular question.  flipping a coin is always an independent event, so it doesn't matter what happens before it.  In the case of this LSAT question, since about half are approved, knowing how many have not been approved could make a difference, but only if you know the total amount that are being considered in the first place.

#### EarlCat

• 2080
• i'm in ur LSAT blowin' ur curve
##### Re: Can anyone explain this flaw question?
« Reply #6 on: January 19, 2010, 03:21:08 PM »

The answer choice doesn't need to say "will be approved" because it's talking about the likelihood that the next budget proposal will be turned down.  This probability can be zero, in which case the next proposal will be approved, or it could be as much as 100 in which case the next proposal will not be approved. Hence, stating the "likelihood that the next budget proposal will be turned down" is the same as saying "...will be approved".

Yes.

Quote
The answer choice is simply stating that the last five budget proposals being turned down does not have any effect on what will happen next.  This is mainly due to the fact that we don't know the total number of budget proposals.

No.

This is not a probability question in a strict coin-flipping, mathematical sense (this is not the GMAT).  We have no idea whatsoever how a budget proposal is evaluated.  Therefore, the result of the last five budget proposals might have an effect on the likelihood the current proposal will be approved.  And it might have this effect regardless of the total number of budget proposals.  We simply don't have enough information to say either way.

The only important thing about this argument is that it "presumes, without warrant," (i.e. makes a necessary assumption) that the results of the last five proposals will affect the results of the next one.

#### EarlCat

• 2080
• i'm in ur LSAT blowin' ur curve
##### Re: Can anyone explain this flaw question?
« Reply #7 on: January 27, 2010, 09:47:41 PM »
If the total number of proposals is 11 and about half of the proposals are approved, and 5 are already turned down, isn't it very likely that the next one is going to be approved?  In this case, the argument is justified.  Since we don't know the total number, we can't say for sure whether the last 5 proposals being turned down is important.

Edit: It is possible that there's a situation for budget proposals where a rulebook might say if the last five budget proposals were rejected, the next one must be approved.  But this is out of the scope of the argument; the argument only states that about half are approved.  The basic reasoning above is within the boundaries for the LSAT.

#### ryanjm

• 299
##### Re: Can anyone explain this flaw question?
« Reply #8 on: January 30, 2010, 07:32:28 AM »
I think "changed name" and earlcat are on the money here. My first instinct was using changed name's reasoning, and it would lead you to the correct answer. Earlcat's explanation is even more precise though imo and the wording of what he said is very likely exactly what the lsat would use as the correct answer.

#### llsatt1

##### Re: Can anyone explain this flaw question?
« Reply #9 on: January 30, 2010, 01:13:49 PM »
I think "changed name" and earlcat are on the money here. My first instinct was using changed name's reasoning, and it would lead you to the correct answer. Earlcat's explanation is even more precise though imo and the wording of what he said is very likely exactly what the lsat would use as the correct answer.

no insult to "changed name" but the discussion of probability in the way he described it is completely irrelevant.  Since about half are approved there is a dependency between the denied and approved sets.

Earlcat's explanation is out of scope.  There is no reason to believe we need more information about the procedures of budget approval.  Either it is approved or it isn't.  Assuming there is more information to budget approval is the type of out of scope thinking LSAC does not want you to do.

The reasoning is simple.  If you know the total number of budget requests and you know how many have been denied then you might be able to make a reasonable judgment as to whether the next one might be approved.  Let's say there are 100 requests and 5 have been denied, then there is no reason to believe the next one will be approved.  This weakens the argument.  Let's say there are 10 requests and the last 5 are denied then the next one will likely be approved.  The fact is we don't know the total number so we cannot just assume the next one will be approved on the basis of the last five being denied.