A certain list of 100 data has a mean of 6 and a standard deviation of d, where d is positive. Which of the following pairs of data, when added to the list, must result in a list of 102 data with a standard deviation of less than d?
A) -6 and 0
B) 0 and 0
C) 0 and 6
D) 0 and 12
E) 6 and 6
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Standard Deviation
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Bens4vcobra
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Frankenstein
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Hi,
The closer the items(to the mean) we add to the list, the more the standard deviation decreases. Here 6 and 6 are the closest to the mean.
Hence, E
The closer the items(to the mean) we add to the list, the more the standard deviation decreases. Here 6 and 6 are the closest to the mean.
Hence, E
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testprepDublin
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Standard deviation is lowest when data points are close to the mean. Therefore when adding new data, the closer the new data is to the previous mean the lower the new standard deviation will be.
The answer is E. This is because by adding new data identical to the mean, the overall 102 data list becomes more condensed (thus decreasing the standard deviation).
The answer is E. This is because by adding new data identical to the mean, the overall 102 data list becomes more condensed (thus decreasing the standard deviation).
Deirdre at testprepdublin.com
