- A4.2%
- B25%
- C16.67%
- D20%
Step-by-Step Solution
A uniform percentage increase raises the mean by the same percentage: . (16.67% divides by the new mean.)
Answer: D) 20%
Nine observations have a mean of 21. Every observation is increased by the same percentage and the new mean is 25.2. By what percentage was each observation increased?
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