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urooj.khan
 
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for a certain race, 3 teams were allowed to enter

by urooj.khan Sat Jun 13, 2009 6:33 pm

for a certain race, 3 teams were allowed to enter 3 members each. A team earned 6-n points whenever one of its members finished in the nth place, where 1<=n<=5. There were no ties, disqualifications or withdrawals. if no team earned more than 6 points, what is the least possible score a team could have earned.

a) 0
b) 1
c) 2
d) 3
d) 4

the correct answer is D.
this is how i got this answer......
since there are 3 teams, each team would come in either first, second or third. the team that comes in third will be the one with the least points.. the points would equal 6 - 3 for this team, which is 3.

is this the correct rationale?
stock.mojo11
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Re: for a certain race, 3 teams were allowed to enter

by stock.mojo11 Sun Jun 14, 2009 10:33 am

urooj.khan Wrote:for a certain race, 3 teams were allowed to enter 3 members each. A team earned 6-n points whenever one of its members finished in the nth place, where 1<=n<=5. There were no ties, disqualifications or withdrawals. if no team earned more than 6 points, what is the least possible score a team could have earned.

a) 0
b) 1
c) 2
d) 3
d) 4

the correct answer is D.
this is how i got this answer......
since there are 3 teams, each team would come in either first, second or third. the team that comes in third will be the one with the least points.. the points would equal 6 - 3 for this team, which is 3.

is this the correct rationale?


I am not sure I understood what you did. Here is what I did

9 members in race. no points for standing 6th-9th positions in race.

That means 5 points for first place and 1 point for 5th place

5,4,3,2,1 respectively.

To minimize the number of points for one team max others. no team scored more than 6. 5+1 and 4+2 max two teams score. 3 is left out, the min other team could score.
RonPurewal
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Re: for a certain race, 3 teams were allowed to enter

by RonPurewal Mon Jun 15, 2009 11:00 pm

the main takeaway here is the same as the main takeaway from the "voltage readings" problem, also posted by you today:

TAKEAWAY:

when you have numbers with a fixed sum or product:

if you want to MINIMIZE A QUANTITY, then you must MAXIMIZE ALL OTHER QUANTITIES in the sum or product.

if you want to MAXIMIZE A QUANTITY, then you must MINIMIZE ALL OTHER QUANTITIES in the sum or product.


--

in this problem:

as the above poster has mentioned, the given description of the point system is cryptic, but you should decode it:
the numbers of points awarded are 5, 4, 3, 2, and 1.

therefore, there is a TOTAL OF 15 POINTS.

we want to MINIMIZE the number of points awarded to any one team.

according to the above takeaway, this means that we should MAXIMIZE the number of points awarded to the OTHER teams.

per the restrictions given, the other teams can receive a maximum of 6 points apiece, so, 15 - 6 - 6 = 3.

(you should probably verify that this is indeed possible, as the above poster has done.)
rockrock
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Re: for a certain race, 3 teams were allowed to enter

by rockrock Sat Aug 28, 2010 7:33 pm

for this problem i just added the "minimum" amount of points one team could receive --- so if each team member got 5th place...it would be 6-5=1 times 3.. is this method flawed?
sandeep.19+man
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Re: for a certain race, 3 teams were allowed to enter

by sandeep.19+man Tue Aug 31, 2010 2:22 am

rockrock Wrote:is this method flawed?

Yes. The question says "There were no ties"
RonPurewal
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Re: for a certain race, 3 teams were allowed to enter

by RonPurewal Thu Sep 16, 2010 7:29 am

sandeep.19+man Wrote:
rockrock Wrote:is this method flawed?

Yes. The question says "There were no ties"


yep.

in fact, if you ever think that the solution to an official problem is this simple, then you are pretty much always going to be wrong; this is just not the way in which the problems are written, even at the most elementary levels.

therefore, if you encounter a "solution" that is this simple, you should think twice before picking that answer.
Borja
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Re: for a certain race, 3 teams were allowed to enter

by Borja Tue Mar 20, 2012 7:04 am

Ron,

this problem appeared to me in a test simulation platform I am using. I answered 3 and... it was wrong!!

The reason is pretty simple (once you see the answer): There can be no ties! So it is not possible to maximize the points of two teams to have 6 points each. They must have 6 points one and 5 points the other one. This leaves 4 points free for the third team. So the correct answer is 4.

Congrats if someone gets this right for the first time. I am really surprised (and angry) about how tricky can this exam be...

Regards,

Borja.
RonPurewal
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Re: for a certain race, 3 teams were allowed to enter

by RonPurewal Fri Mar 23, 2012 10:40 am

Borja Wrote:Ron,

this problem appeared to me in a test simulation platform I am using. I answered 3 and... it was wrong!!


then your "simulation platform" was wrong. what platform would that be?

The reason is pretty simple (once you see the answer):


one golden rule of this forum is that, whenever anyone calls something "simple" or "easy", almost invariably whatever that person writes turns out to be wrong. (a nice lesson in humility)

There can be no ties! So it is not possible to maximize the points of two teams to have 6 points each.


this is incorrect.

when the problem states that there are no ties, that means that there are no ties between/among individual runners in the race. i.e., only one runner got 1st place, only one runner got 2nd place, etc.
under those circumstances, it's still possible for two teams to earn six points:
* one team can get 1st place (= 5 points) and 5th place (= 1 point).
* one team can get 2nd place (= 4 points) and 4th place (= 2 points).
that leaves only 3rd place for the last team, which will thus earn 3 points.

Congrats if someone gets this right for the first time. I am really surprised (and angry) about how tricky can this exam be...


actually, one remarkable characteristic of the real gmat (as opposed to your flawed "simulation platform", whichever that might be) is that it has no "trick questions".
there are certainly questions on which you must read very carefully, and must double-check to make sure you're obeying all the conditions -- but there aren't really questions that stick their proverbial foot out and trip you up. (if there were such a question, it would get thrown out while it was still experimental -- it wouldn't have the right profile of right and wrong answers.)

on the other hand, if you are using practice-test software with incorrect answers in the key, then ... ya, that's tricky. |:

good luck.