- A18
- B32.73
- C36
- D39
Step-by-Step Solution
After the variance is , so the squared deviations add to 360. The extra value sits at the mean, adding nothing: . (39 wrongly adds 3 to the variance.)
Answer: B) 32.73
Ten observations have variance 9. Each is multiplied by 2 and then 3 is added; after that, one more observation equal to the new mean is included. What is the variance of the 11 observations?
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