amorphous wrote:

A research computed the mean, the median and the standard deviation for a set of performance scores. If 5 were to be added to each score, which of these three statistics would change?

A)The mean only

B)The median only

C)The standard deviation only

D)The mean and the median

E)The mean and the standard deviation

src: orbit test prep

Let's

test a set of performance scores.

Let's say the scores are {4, 4, 4}

Here the median = 4, the mean = 4 and the standard deviation = 0

When we add 5 to each score, we get the NEW set {9, 9, 9}

Here the median = 9, the mean = 9 and the standard deviation = 0

Notice that the mean and median changed, but the standard deviation did NOT change.

Answer: D

Cheers,

Brent

_________________

Brent Hanneson – Creator of greenlighttestprep.com

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