hard question!

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hard question!

by bupbebeo » Tue Apr 13, 2010 4:19 am
Ditrama is a federation made up of three autonomous regions. Korva, Mitro, and Guadar. Under the federal revenue-sharing plan, each region receives a share of federal revenues equal to the share of the total population of Ditrama residing in that region, as shown by a yearly population survey. Last year, the percentage of federal revenues Korva received for its share decreased somewhat even though the population survey on which the revenue-sharing was based showed that Korva's population had increased.

If the statements above are true, which one of the following must also have been shown by the population survey on which last year's revenue-sharing in Ditrama was based?

A. Of the three regions, Korva had the smallest number of residents.
B. The population of Korva grew by a smaller percentage than it did in previous years.
C. the populations of Mitro and Guadar each increased by a percentage that exceeded the percentage by which the population of Korva increased.
D. Of teh three regions, Korva's numerical increase in Population was the smallest
E. Korva's population grew by a smaller percentage than did the population of at least one of the other two autonomous region.
Source: — Critical Reasoning |

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by kevincanspain » Tue Apr 13, 2010 4:27 am
If E were false, then K's share of the population could have have fallen and thus nor could its share of the revenues. Since its share did fall, E must be true.

Nice question, what is the source?
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by CrazyGmatter » Tue Apr 13, 2010 5:18 am
@kevin..

I chose D...Can u please elaborate on why you chose E..

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by kevincanspain » Tue Apr 13, 2010 6:11 am
bupbebeo wrote:Ditrama is a federation made up of three autonomous regions. Korva, Mitro, and Guadar. Under the federal revenue-sharing plan, each region receives a share of federal revenues equal to the share of the total population of Ditrama residing in that region, as shown by a yearly population survey. Last year, the percentage of federal revenues Korva received for its share decreased somewhat even though the population survey on which the revenue-sharing was based showed that Korva's population had increased.

If the statements above are true, which one of the following must also have been shown by the population survey on which last year's revenue-sharing in Ditrama was based?

A. Of the three regions, Korva had the smallest number of residents.
B. The population of Korva grew by a smaller percentage than it did in previous years.
C. the populations of Mitro and Guadar each increased by a percentage that exceeded the percentage by which the population of Korva increased.
D. Of teh three regions, Korva's numerical increase in Population was the smallest
E. Korva's population grew by a smaller percentage than did the population of at least one of the other two autonomous region.
The information presented in the text might seem contradictory.

On the one hand, each region receives a share of revenues equal to the share of the total population of Ditrama residing in that region.
On the other hand, Korva's population increased (according to the offical survey).

How could both be true? The population of K, but not its share of the total, has increased. For this to happen, it must be that at least one of the other regions saw a greater percentage increase in population. D need not be true, as we are talking about percentages, not absolute figures. If K's population were larger than that of the other two regions combined, D could easily be false
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by kevincanspain » Tue Apr 13, 2010 6:40 am
Nor can we conclude that K's population increase was the smallest in percentage terms, as C indicates. We only know that it cannot be the largest in %terms

For example

Last This
K 100 110 (from 40% to about 30% of total)
M 100 105
G 200 500
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by harshavardhanc » Tue Apr 13, 2010 10:01 am
bupbebeo wrote:Ditrama is a federation made up of three autonomous regions. Korva, Mitro, and Guadar. Under the federal revenue-sharing plan, each region receives a share of federal revenues equal to the share of the total population of Ditrama residing in that region, as shown by a yearly population survey. Last year, the percentage of federal revenues Korva received for its share decreased somewhat even though the population survey on which the revenue-sharing was based showed that Korva's population had increased.

If the statements above are true, which one of the following must also have been shown by the population survey on which last year's revenue-sharing in Ditrama was based?

A. Of the three regions, Korva had the smallest number of residents.
B. The population of Korva grew by a smaller percentage than it did in previous years.
C. the populations of Mitro and Guadar each increased by a percentage that exceeded the percentage by which the population of Korva increased.
D. Of teh three regions, Korva's numerical increase in Population was the smallest
E. Korva's population grew by a smaller percentage than did the population of at least one of the other two autonomous region.
https://www.beatthegmat.com/ditrama-popu ... 50545.html
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by deepesh.gupta » Sat Apr 17, 2010 4:42 am
Hi KEvin,

I opted for C becase that only gives 100% gaurantee that K's share in revenue would decrease. While in E, the lower increase in one can offset the higher increase in other, keeping the K's share same or even more. Could you please elaborate on why C is wrong.

BTW, what is OA?

kevincanspain wrote:Nor can we conclude that K's population increase was the smallest in percentage terms, as C indicates. We only know that it cannot be the largest in %terms

For example

Last This
K 100 110 (from 40% to about 30% of total)
M 100 105
G 200 500