to a grading error

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to a grading error

by sanju09 » Wed Jul 07, 2010 3:57 am
For a class test, the mean score was 65, the median score was 71, and the standard deviation of the scores was 7. The teacher decided to add 5 points to each score due to a grading error. Which of the following statements must be true for the new scores?
I. The new mean score is 70.
II. The new median score is 76.
III. The new standard deviation of the scores is 12.
(A) None
(B) I only
(C) II only
(D) I and II only
(E) I, II, and III
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by kvcpk » Wed Jul 07, 2010 4:03 am
When all values are increased by a common value,
the mean and median will change .
Bur the standard deviation will remian constant

pick D

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by kvcpk » Wed Jul 07, 2010 4:07 am
When all values are increased by a common value,
the mean and median will change .
Bur the standard deviation will remian constant

pick D