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This topic is locked. If you want to discuss this question please repost it in the respective forum. Set S consists of distinct numbers such that the difference between any two different elements of set S is an integer. How many elements does set S contain? 1. The difference between any two different elements of set S is 2 2. The range of set S is 2 Source: GMAT Club Tests  hardest GMAT questions REVISED VERSION OF THIS QUESTION IS HERE: m1475340.html#p1336423



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Re: GMATCLUB M14#18 [#permalink]
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02 Feb 2009, 22:11
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topmbaseeker wrote: Set S consists of distinct numbers such that the difference between any two different elements of set S is an integer. How many elements does set S contain?
1. The difference between any two different elements of set S is 2 2. The range of set S is 2 A. 1. If the difference between any two different elements of set S is 2, then there are two elements in the set S. If gthere are more than 2 elements, the the diff. betweeen any two diffeent elements would not be 2. so suff. 2. If the range of set S is 2, there could be 2 or 3 elements in the set S. For ex: If the elements are 1.5 and 3.5, the range is 2 and it has 2 elements. If the elements are 1, 2 and 3, the range is 2 and there are 3 elements. so nsf..
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Re: GMATCLUB M14#18 [#permalink]
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03 Feb 2009, 01:41
It should be B.
From stmt1, the elements could be 1.1, 3.1, 5.1, 7.1, 9.1,......and so on.
From stmt2: the elements could be 0.1, 1.1, 2.1 or any such other combination. Hence, the number of elements will always be three.



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Re: GMATCLUB M14#18 [#permalink]
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03 Feb 2009, 01:47
scthakur wrote: From stmt1, the elements could be 1.1, 3.1, 5.1, 7.1, 9.1,......and so on. 1. The difference between any two different elements of set S is 2 In your example, 9.11.1=8 (not 2). So, it doesn't work. scthakur wrote: From stmt2: the elements could be 0.1, 1.1, 2.1 or any such other combination. Hence, the number of elements will always be three. set {0,2} also satisfies second condition but the number of elements is 2.
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Re: GMATCLUB M14#18 [#permalink]
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03 Feb 2009, 01:50
walker wrote: scthakur wrote: From stmt1, the elements could be 1.1, 3.1, 5.1, 7.1, 9.1,......and so on. 1. The difference between any two different elements of set S is 2 In your example, 9.11.1=8 (not 2). So, it doesn't work. scthakur wrote: From stmt2: the elements could be 0.1, 1.1, 2.1 or any such other combination. Hence, the number of elements will always be three. set {0,2} also satisfies second condition but the number of elements is 2. Thanks walker! I completely missed it. I agree with A.



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Re: M14 #18 [#permalink]
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01 Mar 2010, 06:12
topmbaseeker wrote: Set S consists of distinct numbers such that the difference between any two different elements of set S is an integer. How many elements does set S contain? 1. The difference between any two different elements of set S is 2 2. The range of set S is 2 Source: GMAT Club Tests  hardest GMAT questions Its A as from statement 1 it can said that there are two elements and their difference is 2.



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Re: GMATCLUB M14#18 [#permalink]
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01 Mar 2010, 08:04
scthakur wrote: walker wrote: scthakur wrote: From stmt1, the elements could be 1.1, 3.1, 5.1, 7.1, 9.1,......and so on. 1. The difference between any two different elements of set S is 2 In your example, 9.11.1=8 (not 2). So, it doesn't work. scthakur wrote: From stmt2: the elements could be 0.1, 1.1, 2.1 or any such other combination. Hence, the number of elements will always be three. set {0,2} also satisfies second condition but the number of elements is 2. Thanks walker! I completely missed it. I agree with A. My big problem is not completely reading the question and understanding what it is actually asking for. I read gmatexperiencetips76051q44v60awa89590.html and now I read the question 2 times before ever looking at any of the answers. Early on I would seem to answer the wrong question a lot. Just reading the question twice and then rereading it again after I have my answer has helped me catch a lot of gotchas in my practice questions. Hope that helps.



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Re: M14 #18 [#permalink]
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01 Mar 2010, 13:11
Could someone please explain how they obtained A?
How does that entail how many distinct integers in a set?
Thanks



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Re: M14 #18 [#permalink]
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03 Mar 2010, 07:05
any set can have only 2 elements if the difference between any two of the elements are same
ex: s1 ={4,2} difference bewteen them is 2 s1= {4,2,4} then if we choose 4,4 then diff will be 0
so ans is A



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Re: M14 #18 [#permalink]
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13 Mar 2010, 10:24
1 => for difference between any two elements to be 2 there must be only 2 elements in the set. Hence this is sufficient. 2 => Range can be the same for a sets with different number of elements Therefore 1 is sufficient.
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Re: M14 #18 [#permalink]
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05 Mar 2011, 01:23
Answer is A because range will not tell how many different elements are there in domain.



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Re: M14 #18 [#permalink]
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30 Mar 2011, 23:29
1. The difference between any two different elements of set S is 2
If ab=2 then ba=2, so S is an empty set.



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Re: M14 #18 [#permalink]
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25 Jun 2011, 00:12
If set a is {4,2} then the difference between the 2nd number and the first number is not 2 but 2. Hence its insufficient. Can someone please enlighten. Should the question statement not say mod of the difference between any two different elements of set is 2 ?
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Re: M14 #18 [#permalink]
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07 Mar 2012, 07:50
I had seen a very similar question before. This allowed me to get to answer A relatively quickly. Good question!



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Re: M14 #18 [#permalink]
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26 Apr 2012, 04:44
topmbaseeker wrote: Set S consists of distinct numbers such that the difference between any two different elements of set S is an integer. How many elements does set S contain? 1. The difference between any two different elements of set S is 2 2. The range of set S is 2 Source: GMAT Club Tests  hardest GMAT questions 1: how to get any two diffferent elements is 2... we cant get 2 as difference between any two different elements if we have more than 2 elements... take any example , u cant come with a 3 element set where there difference between any two element is 2.. can we? i am doubtful on it... so 1 is SUFFICIENT 2: range is 2, does not mean only 2 elements.. this is known by all... hence Not sufficient hence A is my answer.. can somebody tell me if this is fine?
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Re: M14 #18 [#permalink]
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15 May 2013, 13:38
It seems that i can't get any set where the difference between any two numbers is equal to 2. Statement 1 cannot be sufficient by itself. Can someone please give me an example of a set containing TWO numbers where their difference is always equal to 2. Thanks
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Re: M14 #18 [#permalink]
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15 May 2013, 14:09
Rock750 wrote: It seems that i can't get any set where the difference between any two numbers is equal to 2. Statement 1 cannot be sufficient by itself.
Can someone please give me an example of a set containing TWO numbers where their difference is always equal to 2.
Thanks Consider set \(S={0,2}\) The difference between the elements is 2. The question says that S contains distinct integers, and A says that the difference between any two elements is 2. now consider set M for example \({0,2,4}\) This respect the question (distinct integers) but goes against A (the difference between 0 and 4 is 4, not 2) With A we can enstablish that the set has only two elements. Is it clear? let me know
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Re: M14 #18 [#permalink]
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15 May 2013, 17:00
Zarrolou wrote: Rock750 wrote: It seems that i can't get any set where the difference between any two numbers is equal to 2. Statement 1 cannot be sufficient by itself.
Can someone please give me an example of a set containing TWO numbers where their difference is always equal to 2.
Thanks Consider set \(S={0,2}\) The difference between the elements is 2. The question says that S contains distinct integers, and A says that the difference between any two elements is 2. now consider set M for example \({0,2,4}\) This respect the question (distinct integers) but goes against A (the difference between 0 and 4 is 4, not 2) With A we can enstablish that the set has only two elements. Is it clear? let me know Hey Zarrolou If you consider the set \(S={0,2}\) , the difference between ANY two elements you will get will not equal to 2. For instance, 2  0 = 0 BUT 02 = 2 SO the difference between 0 and 2 is not equal to 2. I think the stem would have been much clearer if it stated the positive difference instead don't you think ?
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Re: M14 #18 [#permalink]
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25 Feb 2014, 07:07
topmbaseeker wrote: Set S consists of distinct numbers such that the difference between any two different elements of set S is an integer. How many elements does set S contain? 1. The difference between any two different elements of set S is 2 2. The range of set S is 2 Source: GMAT Club Tests  hardest GMAT questions m14 q18If set \(S\) contains more than 1 element, how many elements does set \(S\) contain?(1) The difference between any two elements of set \(S\) is 2 > since the difference between ANY two elements is 2 then there cannot be more than 2 elements in the set, else we could select some particular two elements whose difference wouldn't be 2. Sufficient. (2) The range of set \(S\) is 2. Clearly insufficient, consider: S={0, 2} and S={0, 0, 2}. Answer: A.
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Re: M14 #18 [#permalink]
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27 Apr 2014, 01:30
1) Different between any 2 element is 2: we need at least 2 elements, for instance a and b (a<b). Now suppose we have a third one (c): if c<a > bc>2 if c>a > bc<2 if c=a > ca = 0 All three scenarios above does not satisfy stat 1) > only 2 elements > sufficient 2) Range of set is 2: we can have {1,3} and {1,2,3} that both satisfy the requirement > insufficient
Choose A











