- AMean 38.92, SD 5
- BMean 41.08, SD 5.20
- CMean 38.92, SD 4.80
- DMean 38.92, SD 5.20
Step-by-Step Solution
Correct sum , mean , corrected . Variance , SD . (The SD does change when a value is corrected.)
Answer: D) Mean 38.92, SD 5.20
Twenty-five values have mean 40 and SD 5. It is later found that a value recorded as 52 should have been 25. What are the correct mean and SD?
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