If every observation in a data set is multiplied by -3, what happens to its standard deviation?
Correct answer: B. It becomes three times as large
- A. It becomes one-third as large
- B. It becomes three times as large
- C. It remains unchanged
- D. It becomes negative three times as large
Explanation
Standard deviation is multiplied by the absolute value of the multiplying constant. Therefore, multiplying every observation by -3 makes the standard deviation three times as large, not negative.
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