tejal777 wrote:

Hey guys I get a little confused when I am faced with a set containng only one element so thought will meke it clear once and for all:

{-5}

Mean:-5

Median: ??? (explanations?)

Mode:-5 or none

Range:0

Standard Deviation:0

Set with identical values:

Range=0,S.D=0

Inputs??

I don't think I've ever seen a one-element set in a GMAT question, but the median of the set {-5} is -5, because that's the 'middle number' -- it's the only number, so it must be in the middle. If each element in a set occurs with equal frequency, the set has no mode, so this set has no mode, though that's a technicality that you will never need to worry about in a GMAT question.

If a set has more than one element, and all values are equal to some number x, then the range and s.d. are both zero, and the mean, median and mode are all equal to x.

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