Gurby & Gus

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Gurby & Gus

by Amrabdelnaby » Sun Dec 27, 2015 7:32 am
I always get confused in these kind of problems and end up spending too much time on them and still getting the answer wrong!

If you could please explain to me the solution and the concept/methodology I should use when tackling these kind of questions, I would be thankful :)

After an attempted breakout at Folsom State Prison, the warden lines the prisoners up for a headcount. (Assume the warden counts correctly and that no prisoners switch positions or leave/escape during either headcount.) When the warden counts from left to right, Gurby is the 20th prisoner counted, but when the warden counts from right to left, Gus is the 20th prisoner counted. How many prisoners are lined up for the headcount?

(1) There are 13 prisoners between Gurby and Gus.

(2) The total number of prisoners is odd.

Statement (1) ALONE is sufficient, but statement (2) alone is not sufficient to answer the question asked
Statement (2) ALONE is sufficient, but statement (1) alone is not sufficient to answer the question asked
Both statements (1) and (2) TOGETHER are sufficient to answer the question asked; but NEITHER statement ALONE is sufficient
EACH statement ALONE is sufficient to answer the question asked
Statements (1) and (2) TOGETHER are NOT sufficient to answer the question asked, and additional data specific to the problem are needed

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by [email protected] » Sun Dec 27, 2015 8:01 am
Hi Amrabdelnaby,

There is a 'visual component' to certain types of GMAT questions, so it often helps to draw pictures so that you can physically see the possibilities. You could probably answer this type of question faster using that type of approach (than say, trying to work algebraically).

There's a brief discussion of this question here:

https://www.beatthegmat.com/prisoners-t287172.html

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