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Set A = , If the median is x/2, what is x [#permalink]
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29 Jan 2008, 13:17
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This topic is locked. If you want to discuss this question please repost it in the respective forum. Set A = [x, 1, 1, 3, x], If the median is x/2, what is x?
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Re: median [#permalink]
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29 Jan 2008, 13:24
bmwhype2 wrote: Set A = [x, 1, 1, 3, x], If the median is x/2, what is x? are these in order by value? or is it just random? I don't see how it could be in order by value b/c that would mean x/2=1 and x=2, which wouldnt make any sense at all. I get 0=x b/c if we have 1,x... then x must be less than 1 so> 1,x,x,1,3 thus x=x/2 > 2x=x Only way this can be is if x=0.



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Re: median [#permalink]
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29 Jan 2008, 13:25
I am assuming x is an integer.
If the median of a set of 5 integers is x/2, then x/2 is the "middle" integer when all integers are arranged in increasing order.
so we have, 1, 1, x/2, 3, x. x must logically be the largest integer in the set if x/2 is the median.
Therefore, x must be 4.
Part of me thinks this was almost too easy, so please correct me if I made a mistake somewhere.



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Re: median [#permalink]
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29 Jan 2008, 13:32
Set A = [x, 1, 1, 3, x] Set A have 5 numbers, Therefore, median is defined by one number: 1 or x (x<1) 1) x/2=1 ==> x=2 2) x/2=x ==> x=0
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Re: median [#permalink]
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29 Jan 2008, 13:33
Wait, so Set A is already arranged in increasing order?



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Re: median [#permalink]
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29 Jan 2008, 13:39
walker wrote: Set A = [x, 1, 1, 3, x]
Set A have 5 numbers, Therefore, median is defined by one number: 1 or x (x<1)
1) x/2=1 ==> x=2 2) x/2=x ==> x=0 can you elaborate? if x=0, then 0/2 because median is is x/2
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Re: median [#permalink]
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29 Jan 2008, 13:40
bmwhype2 wrote: Set A = [x, 1, 1, 3, x], If the median is x/2, what is x? can you provide the answer choices? 0 and 2 both seem to work..
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Re: median [#permalink]
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29 Jan 2008, 13:43
incognito1 wrote: bmwhype2 wrote: Set A = [x, 1, 1, 3, x], If the median is x/2, what is x? can you provide the answer choices? 0 and 2 both seem to work.. this is part of a DS question. both are correct. i just want to see how the answer came about.
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Re: median [#permalink]
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29 Jan 2008, 13:45
I guess choices are like I. 0 II 1 III 2 A only I B only II C I and III D II and III E I, II and III
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Re: median [#permalink]
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29 Jan 2008, 13:47
walker wrote: Set A = [x, 1, 1, 3, x]
Set A have 5 numbers, Therefore, median is defined by one number: 1 or x (x<1)
1) x/2=1 ==> x=2 2) x/2=x ==> x=0 Ah yes, 2 can be an answer as well. 2,1,1,2,3 And thus 2/2=1 is the median. or 1,0,0,1,3. But in either case the original is not in the correct increasing order. Haven't done a question quite like this before. whats the source?



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Re: median [#permalink]
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29 Jan 2008, 14:39
walker wrote: I guess choices are like I. 0 II 1 III 2 A only I B only II C I and III D II and III E I, II and III lol didn't realize this was a DS question
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Re: median [#permalink]
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29 Jan 2008, 20:29
i just assumed that set was already in increasing order. since there are an odd number of terms, the median is equal to 1, and if 1=x/2, that leads to x=2 .... am i oversimplifying this q ?



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Re: median [#permalink]
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05 Feb 2008, 06:17
walker wrote: Set A = [x, 1, 1, 3, x]
Set A have 5 numbers, Therefore, median is defined by one number: 1 or x (x<1)
1) x/2=1 ==> x=2 2) x/2=x ==> x=0 thanks. finally figured out the logic...
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Re: median [#permalink]
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05 Feb 2008, 07:52
bmwhype2 wrote: Set A = [x, 1, 1, 3, x], If the median is x/2, what is x? x >= 0 because there are at least 3 numbers that are greater or equal than 0 and x/2 is the median. 1) x  median > x = x/2 > x = 0 2) 1  median > x/2 = 1 > x = 2 there are no other options because the median is greater or equal than zero and it can't be equal to 3 because there are at least 3 numbers smaller than 3.



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Re: median [#permalink]
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05 Feb 2008, 15:07
I assumed this set wasn't in order. and the value of x was the same integer. for x equals 2 and x = 2. so I rearranged..
Set A = ( 2, 1, 1, 2, 3)
Median being 1.










