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Set S consists of even number of integers. Is the median of [#permalink]
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26 Jul 2008, 18:51
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Set S consists of even number of integers. Is the median of set S negative?
1. Exactly half of all elements of set S are positive 2. The biggest negative element of set S is 1



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Re: DS Median [#permalink]
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26 Jul 2008, 19:21
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aaron22197 wrote: Set S consists of even number of integers. Is the median of set S negative?
1. Exactly half of all elements of set S are positive 2. The biggest negative element of set S is 1 From 1) Two cases are possible: a) when 0 is present in SET S. then (3,2,1,0,5,7) median = +ve (9,7,3,2,0,9,11,13) median = +ve b) when 0 is not present in SET S. then (3,2,1,2,4,6) median = ve (9,7,3,2,1,5,7,9) median = +ve Thus NO Definite answer can be determined from 1) From 2) Two cases are possible: a) when 0 is present in SET S. (3,2,0,1,2,3) median = ve (3,2,1,0,2,3) median = +ve Thus NO Definite answer can be determined from 2) Combining 1) and 2) Two cases are possible: a) when 0 is present in SET S. then (3,2,1,0,5,7) median = +ve b) when 0 is not present in SET S. (3,2,1,1,4,6) median = 0 (5,3,2,1,5,7) median = +ve Thus a definite answer NO median of set S cant be negative. Thus C is the answer.



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Re: DS Median [#permalink]
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27 Jul 2008, 22:42
aaron22197 wrote: Set S consists of even number of integers. Is the median of set S negative?
1. Exactly half of all elements of set S are positive 2. The biggest negative element of set S is 1 as the total number of elements is even, the condistions should satisfy when the numbers of elements is only two statement 1 (0,1)  median +ve (1,1)  median 0 (2,1)  median ve Not suff statement 2 (1,0) median ve (1,1) median 0 (1, 2) median +ve Not suff combine (1,1) median 0 (1,2) median +ve Suff ... as median is not negative in any case ... option C



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Re: DS Median [#permalink]
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28 Jul 2008, 00:23
aaron22197 wrote: Set S consists of even number of integers. Is the median of set S negative?
1. Exactly half of all elements of set S are positive 2. The biggest negative element of set S is 1
as the total number of elements is even, the condistions should satisfy when the numbers of elements is only two
statement 1 (0,1)  median +ve (1,1)  median 0 (2,1)  median ve Not suff
statement 2 (1,0) median ve (1,1) median 0 (1, 2) median +ve Not suff
combine (1,1) median 0 (1,2) median +ve Suff ... as median is not negative in any case ... option C
Here, if I take more than 2 elements (say 4), then combining the two can give me a +ve or ve median. Let us take an example here.
(2,1,1,1).
Hence, I will go for E.



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Re: DS Median [#permalink]
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28 Jul 2008, 00:27
scthakur wrote: Here, if I take more than 2 elements (say 4), then combining the two can give me a +ve or ve median. Let us take an example here.
(2,1,1,1).
Hence, I will go for E. median will be zero in this case (1+1)/2.



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Re: DS Median [#permalink]
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28 Jul 2008, 01:34
Oh.....I missed that.....thanks Durgesh79.



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Re: DS Median [#permalink]
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28 Jul 2008, 01:48
Here, if I take more than 2 elements (say 4), then combining the two can give me a +ve or ve median. Let us take an example here.
(2,1,1,1).
Hence, I will go for E.[/quote] For an even number of values, it is the mean of the two middle values. Thus for set (2,1,1,1), median is 0. Source: http://www.purplemath.com/modules/meanmode.htm



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Re: DS Median [#permalink]
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28 Jul 2008, 08:16
aaron22197 wrote: Set S consists of even number of integers. Is the median of set S negative?
1. Exactly half of all elements of set S are positive 2. The biggest negative element of set S is 1 (1) consider Set S: ve, ve, ve, +ve, +ve, +ve Then the median will be equal to the average of the middle two terms. The mediam can be ve, +ve or zero. Not Suff (2) So, in my case, the 3rd term should be 1 3, 3, 3, 1, +2, +10 (median = 2) 3, 3, 1, +3, +5, +10 (median = +1) Not Suff (1) & (2) 10, 9, 1, +1, +2, +3 (median = 0) 10, 9, 1, +9, +2, +3 (median = 4) median will NOT be negative. Suff Ans is C



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Re: DS Median [#permalink]
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28 Jul 2008, 08:20
aaron22197 wrote: Set S consists of even number of integers. Is the median of set S negative?
1. Exactly half of all elements of set S are positive 2. The biggest negative element of set S is 1 Statement 1) is insuff. since mod of smallest positive element can be bigger or smaller then largest ve element Statement 2) is insuff. since two median element can be 0 and 1 as well Combining both median elements can be 0,1 or 1, 1 so median will be 1/2 or 0 which is non ve Answer is C)










