I have a question about the answer to DSQ-32 in the Green Official Guide. The question reads:
Is the value of n closer to 50 than to 75?
1) 75-n > n-50
2) n > 60
The answer to the question is A, however I feel that this answer incorrectly assumes that n is between 50 and 75, the question does not clearly indicate that this indeed the case. Couldn't n be less than 50, like 49? If so then the first statement would not be sufficient.
Am I missing something here?
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- jessdbon
- shaji
Re: OG- Green DS #32
Statement1 implies tha n<62.5 and 62.5 is eqidistant between 50&75; therefore a definite 'yes'
Statement 2 states n>60, so no definitive 'yes' or 'no'
The correct answer is A.
Statement 2 states n>60, so no definitive 'yes' or 'no'
The correct answer is A.
jessdbon Wrote:I have a question about the answer to DSQ-32 in the Green Official Guide. The question reads:
Is the value of n closer to 50 than to 75?
1) 75-n > n-50
2) n > 60
The answer to the question is A, however I feel that this answer incorrectly assumes that n is between 50 and 75, the question does not clearly indicate that this indeed the case. Couldn't n be less than 50, like 49? If so then the first statement would not be sufficient.
Am I missing something here?
- RonPurewal
- Students
- Posts: 19744
- Joined: Tue Aug 14, 2007 8:23 am
Couldn't n be less than 50, like 49? If so then the first statement would not be sufficient.
This isn't an issue. The first statement says that n is less than 62.5 (the midpoint of 50 and 75), as another poster has already pointed out. Draw a number line, put 50, 62.5, and 75 on it, and you'll notice that ANYTHING less than 62.5 is closer to 50 than to 75, no matter where it is. If you insist on treating numbers smaller than 50 as a different case, this ultimately doesn't change the conclusion:
* 60 is closer to 50 than to 75 (this is the type of number you apparently already had in mind)
* 50 itself is closer to 50 than to 75 (distance from 50 is zero, so it must be!)
* Numbers like 0 (and your example, 49) are closer to 50 than to 75. In fact, these numbers are always exactly 25 units closer to 50 than to 75.
Therefore, the first statement is sufficient (it's Yes for all three of the conditions in your trichotomy of <50, =50, and 50<x<62.5).
Hope that helps.
This isn't an issue. The first statement says that n is less than 62.5 (the midpoint of 50 and 75), as another poster has already pointed out. Draw a number line, put 50, 62.5, and 75 on it, and you'll notice that ANYTHING less than 62.5 is closer to 50 than to 75, no matter where it is. If you insist on treating numbers smaller than 50 as a different case, this ultimately doesn't change the conclusion:
* 60 is closer to 50 than to 75 (this is the type of number you apparently already had in mind)
* 50 itself is closer to 50 than to 75 (distance from 50 is zero, so it must be!)
* Numbers like 0 (and your example, 49) are closer to 50 than to 75. In fact, these numbers are always exactly 25 units closer to 50 than to 75.
Therefore, the first statement is sufficient (it's Yes for all three of the conditions in your trichotomy of <50, =50, and 50<x<62.5).
Hope that helps.
- shuba
- Students
- Posts: 10
- Joined: Mon Sep 26, 2011 9:05 am
Re: OG- Green DS #32
great explanation! thanks Ron!
- RonPurewal
- Students
- Posts: 19744
- Joined: Tue Aug 14, 2007 8:23 am
Re: OG- Green DS #32
shuba.personal Wrote:great explanation! thanks Ron!
you're welcome ... 4.5 years later.
this thread is now locked, as it refers to a problem from the official guide. (way back in mid- to late 2007 when this thread was created, gmac had not yet asked us to stop discussing the official guide problems on our forum.)
5 posts Page 1 of 1