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Re M21-02 [#permalink]
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 16 Sep 2014, 01:10
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Re: M21-02 [#permalink]
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04 Oct 2014, 06:26
In option 2, The range (largest - Least )= 2b; how would be arrive at 2b from the set of the three numbers viz : a+b, b-a, a-b ?
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Re: M21-02 [#permalink]
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04 Oct 2014, 09:25
cjhande wrote: In option 2, The range (largest - Least )= 2b; how would be arrive at 2b from the set of the three numbers viz : a+b, b-a, a-b ? It's explained in the solution above: If a = b = 0, then S = {0, 0, 0} --> the range = 0 - 0 = 0 = 2b. If a = 0 and b = 1, then S = {-1, 1, 1} --> the range = 1 - (-1) = 2 = 2b.
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Re: M21-02 [#permalink]
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25 Jul 2016, 05:32
a+b - (a-b) = 2b, which is true for a=b=0 as well. Hence that makes b-a as the median. From first option I got a+b as the median. What am I missing here?
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Re: M21-02 [#permalink]
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05 Sep 2016, 09:56
Option (1) states mean is a+b, which can be inferred from the question stem.
How does this lead a+b to 0? Could someone please clarify?
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Re: M21-02 [#permalink]
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05 Sep 2016, 22:25
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Bunuel wrote: manhasnoname wrote: Option (1) states mean is a+b, which can be inferred from the question stem.
How does this lead a+b to 0? Could someone please clarify? By simplifying this: \(mean=\frac{(a - b)+(b - a)+(a + b)}{3}=a+b\) doesnt simlifying leads to: a+B/3=a+b ????????????
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Re: M21-02 [#permalink]
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07 Sep 2016, 02:05
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Re: M21-02 [#permalink]
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31 Dec 2016, 13:49
I worked the second statement as following: Range= Highest Number - Lowest Number R=2b In order for R to be 2b, the only possible combination is (b+a)-(a-b). Thus, (a-b)≤(b-a)<(b+a) or (a-b)<(b-a)≤(b+a) So b-a is the median. Where am I wrong?
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Re: M21-02 [#permalink]
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01 Jan 2017, 08:18
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Judging by this question, you can't assume that the set provided to you is in ascending order? I'd feel more comfortable removing that assumption if anyone can provide an OG question which has a set of unknown variables not provided in ascending order.
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Re: M21-02 [#permalink]
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11 Feb 2017, 12:22
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Re: M21-02 [#permalink]
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17 Aug 2017, 08:37
Did not understand the inference of 1st option.
How the median of the set is a+b ??
looking at the set median is b-a .
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Re M21-02 [#permalink]
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19 Aug 2017, 05:24
I think this is a high-quality question and the explanation isn't clear enough, please elaborate. Hello expert, I get your explanation for option B, but aren't we worried about finding the mean in terms of a and b.
as explained even if a=b=0 or a=1, b=0, mean is b-a.
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Re: M21-02 [#permalink]
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19 Aug 2017, 05:37
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Re: M21-02 [#permalink]
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06 Nov 2017, 05:47
+1 for A. My take : Statement 1 : Given that mean is a+b. (a+b)/3=a+b ; i.e a+b=0. This means that the set is -2b,0,2b. The median in this case becomes zero. We get a definite answer. Statement 2 : Range is 2b. The middle value is b-a. This is not a definite value. Hence not sufficient. The answer is option A.
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