scoobydooby wrote:D seems better than B as i reread the stimulus.
it says the first term is 3. asks for the 3rd term. the use of "1st" and "3rd" seems to be hinting that the set is ordered.
if {3, y, z} is in increasing order, from stment 1, z must be 3
if {3, y, z} is in decreasing order, from stment 1, z must be 3
stment 1 is sufficient in itself.
If the first term
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sreak1089
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Hi Scoobydooby, stmt # 1 says range is zero => first and last terms are equal to 3. Now the middle term has to be any number between 3 & 3 and only possibility is to be 3 itself. Hence sufficient. But, biggest doubt I have is that the problem stem talks about sets and as far as I know, a set should contain distinct elements. Hence, how can three terms, all be equal to 3?????
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scoobydooby
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hey sreak1089,
the question says "data set". i guess it just implies a collection of numbers. dont think we have to use conventional set theory definitions. the problem would have defined it if we had to use it.
i may be wrong, we shall get to know how to interpret "set" once the OA is out
the question says "data set". i guess it just implies a collection of numbers. dont think we have to use conventional set theory definitions. the problem would have defined it if we had to use it.
i may be wrong, we shall get to know how to interpret "set" once the OA is out
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Ian Stewart
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Just to clarify a few points:madhur_ahuja wrote:{x,y,z}
If the first term in the data set above is 3, what is the third term?
(1) The range of this data set is 0.
(2) The standard deviation of this data set is 0.
-sets are not ordered, so it makes no mathematical sense to talk about the 'first term' or the 'third term' in a set. So the question above is not well-designed - where is it from?
-in statistics, data sets can contain repeated elements. {3, 3, 3} is a perfectly acceptable data set. Most GMAT stats questions are about data sets. The concept of the 'mode', for example, wouldn't make any sense if sets never contained repeated elements;
-if the range of a data set is zero, or if the standard deviation of a data set is zero, all of the elements in the set are equal.
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