- A15
- B14
- C13
- D16
Step-by-Step Solution
Total change , so the mean falls by : new mean 14. (13 forgets the +3 part.)
Answer: B) 14
Twenty observations have a mean of 15. Each of the first 10 is increased by 3 and each of the remaining 10 is decreased by 5. What is the new mean?
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