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joshi.komal
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PostPosted: Sun Jan 20, 2008 4:09 pm    Post subject: Unable to understand these questions on the GMAT Test Prep Reply with quote

Hi Folks,

I am unable to understand these questions on the GMAT Test Prep. I would highly appreciate if someone could throw some light on how to solve then and what should be the general strategy for attacking such types of questions.

Thanks
Komal

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simplyjat
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PostPosted: Sun Jan 20, 2008 8:21 pm    Post subject: Reply with quote

Its better to have one thread per question...
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PostPosted: Sun Jan 20, 2008 8:53 pm    Post subject: Reply with quote

simplyjat,
First and third Qs ahas already been discussed in the forum. However, I am giving my approach as below -
First Qs-
--------

If equally distributed, population of each city will be = 132000/11 = 12000
As population of each city can not be greater than 10% of other city, so in minimum -
12000 = 110x/100 -where x = minimum population of a city
So x ~ 10909... (rounding) 10909.
But this is the minimum amount of population. So D is the closet to chose. IMO D.

Second Qs -
-------------

Three. (First, second), (second, third) and (4,-5).

Third Qs -
-----------

S = 1. Request you to search the forum. Stuart has given a good approach to solve this kind of Qs...

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Stuart Kovinsky
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PostPosted: Mon Jan 21, 2008 6:19 am    Post subject: Reply with quote

For (1), I'd do it by trial and error.

One thing that's important to remember about the GMAT is that no one is allowed a calculator. As a result, if you find yourself doing lots of complicated calculations, you're probably on the wrong track.

We know the 11 numbers average to 12000. 11 is a weird number of terms, there has to be a reason why it was chosen.

Let's keep life as simple as possible and see if we get lucky:

If 10 of the terms were 100 over the average, then the last term would be 1000 under the average (maybe that's why the testmaker chose 11!).

So, the 10 big terms would each be 12100, the smallest term would be 11000.

Hey! 12100 is exactly 10% greater than 11000! We've achieved maximum spread allowed, which means that 11000 is indeed the minimum number we can pick (if we chose any smaller number, then we'd have to make one of the other numbers bigger, which would mean a spread > 10%).

Would this approach get you 10/10 on a highschool math test? No, of course not. However, we need to remember that the GMAT is definitely NOT a highschool math test - we only get credit for the right answer. Finding creative solutions to problems (including picking numbers, a great GMAT strategy) is what will lead to maximum success on test day.

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PostPosted: Mon Jan 21, 2008 7:23 am    Post subject: Reply with quote

@joshi komal .. Please follow forum rules, post just one question per thread. I will be forced to edit your future posts if this rule is not followed.

The rule is here to make it easier for you guys to search for questions. Hope you understand.

Regards Smile
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joshi.komal
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PostPosted: Mon Jan 21, 2008 10:45 am    Post subject: Reply with quote

gabriel wrote:
@joshi komal .. Please follow forum rules, post just one question per thread. I will be forced to edit your future posts if this rule is not followed.

The rule is here to make it easier for you guys to search for questions. Hope you understand.

Regards Smile


Hi Gabriel,

I understand... I will take care in future. ....However you can edit the post if you want Smile

I did not think about ease of searching for other users before posting, My BAD.

Thanks
Komal
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joshi.komal
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PostPosted: Mon Jan 21, 2008 11:18 am    Post subject: Reply with quote

Stuart Kovinsky wrote:
For (1), I'd do it by trial and error.

One thing that's important to remember about the GMAT is that no one is allowed a calculator. As a result, if you find yourself doing lots of complicated calculations, you're probably on the wrong track.

We know the 11 numbers average to 12000. 11 is a weird number of terms, there has to be a reason why it was chosen.

Let's keep life as simple as possible and see if we get lucky:

If 10 of the terms were 100 over the average, then the last term would be 1000 under the average (maybe that's why the testmaker chose 11!).

So, the 10 big terms would each be 12100, the smallest term would be 11000.

Hey! 12100 is exactly 10% greater than 11000! We've achieved maximum spread allowed, which means that 11000 is indeed the minimum number we can pick (if we chose any smaller number, then we'd have to make one of the other numbers bigger, which would mean a spread > 10%).

Would this approach get you 10/10 on a highschool math test? No, of course not. However, we need to remember that the GMAT is definitely NOT a highschool math test - we only get credit for the right answer. Finding creative solutions to problems (including picking numbers, a great GMAT strategy) is what will lead to maximum success on test day.



Hi Stuart/ Spamjet


First of all THANKS a lot guys for your time.

I think I have figured out the solution for this which consists of simple highschool maths without too much calculation.

since no other province can have population > 10% of other state. This simply means that all the states will have population which is 110 % of smallest population which is x. So now we have an equation which is.

x + 10* 1.1 * x = 132000
=> x + 11 x = 132000
=> 12 x = 132000
=> x = 132000/12
=> x = 11000

Thanks
Komal
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