Home › CAT › Quantitative Aptitude › CAT QA — Mixed › If each observation multiplied by 3, SD becomes:
If each observation multiplied by 3, SD becomes:
A3× original
BSquared
C9×
DSame
Answer & Solution
Correct answer: A. 3× original
SD(aX) = |a| × SD(X). Multiplying by 3 multiplies SD by 3. Variance multiplies by 9. Useful for unit conversions.
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