GMAT Prep 1 PS 31

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by camitava » Sun Dec 30, 2007 9:21 pm
starxx68,
Total population = 132,000 Cities = 11
So if equally distributed, each city would have = 12,000 population.
But now if 10% of population can vary in each city.
So minimum range of population that a city can have = (90/100 * 12000) = 10,800 and maximum = (110/100 * 12000) = 13200. So the minimum population that a city can have = 11000. IMO D.
Correct me If I am wrong


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Amitava

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by specialk1975 » Sun Dec 30, 2007 11:05 pm
You can back solve this one:

Take the 11,000

1) 132000 - 11000 = 121,000 "remaining population"
2) 121,000/ 10 (the remaining cities) = 12,100 (per city)
3) (12,100-11,000)/ 11,000 = 10%

*If you take the 10800 choice, you get 12% which is to high.

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by Auzbee » Mon Dec 31, 2007 7:12 pm
So minimum range of population that a city can have = (90/100 * 12000) = 10,800 and maximum = (110/100 * 12000) = 13200. So the minimum population that a city can have = 11000. IMO D.
Amitava,
In your explanation why did you choose 11000 and not 10900?

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by camitava » Mon Dec 31, 2007 11:36 pm
Hey Auzbee! U r right man. It should be 10900 but not 11000. A miss from y side. However thanks Auzbee for pointing out my mistake.
Correct me If I am wrong


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Amitava