Ds /per capita

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Ds /per capita

by mav800rick » Fri Jun 20, 2008 9:01 am
In a demographic study, the population and total income of a certain region were
estimated from other data, and both estimates had lower and upper limits. At the time of
the estimates, was the per capita income for the region greater than $16,500?
(1) The lower limit for the estimate of the population was 330,000 people.
(2) The lower limit for the estimate of the total income was $5,500,000,000.

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OA is E. Could is not be C gievn that we know the estimated minimum per caipta?
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by atlantic » Fri Jun 20, 2008 9:42 am
My choice would have been C also.

If both the lower limit of the population and income are known, then we can determine the minimum 'per capita' income. Or am I wrong?

Unless 'estimated from other data' means that the estimations are not accurate, and so nothing can be calculated using the numbers given in (1) and (2), leading to E. If so, you'll never see a question like that on real GMAT. Or am I wrong again?

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Re: Ds /per capita

by Ian Stewart » Fri Jun 20, 2008 11:15 am
mav800rick wrote:In a demographic study, the population and total income of a certain region were
estimated from other data, and both estimates had lower and upper limits. At the time of
the estimates, was the per capita income for the region greater than $16,500?
(1) The lower limit for the estimate of the population was 330,000 people.
(2) The lower limit for the estimate of the total income was $5,500,000,000.

-----------

OA is E. Could is not be C gievn that we know the estimated minimum per caipta?
I agree entirely with atlantic here: the wording of the question is just bizarre. The question asks what the per capita income was; the data is about estimates. Were the estimates any good? Maybe they're way off. So the answer already must be E, because of the wording of the question.

Still, let's say the word 'estimate' is never used in the question. Instead, say it asks: Is the per capita income greater than $16,500?

1) There were at least 330,000 people.
2) The total amount of money earned by people in the region was at least $5.5 billion.

The answer is still E. Perhaps we have exactly 330,000 people, and they earned several trillion dollars combined- the per capita income could be very high, as high as you like. Or, perhaps they 'only' earned $5.5 billion, but perhaps there are 5.5 billion people in the region. Then the per capita income would be $1.
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by durgesh79 » Sat Jun 21, 2008 7:04 am
lets simplfy this question.

Q is x/y > 16500

statement 1 : y > 330,000
statement 2 : x > 5.5 M

to know least value of x/y we need min(x) and max(y) ......

we have both min(x) and min(y) .... so not suff ... E