Statisticsmedium · Past Paper
If the mean of 5 observations is 15 and the mean of 10 other observations is 20, the combined mean is:
A17.5
B18.33
C16.66
D19
✓ Correct Answer: B — 18.33
Combined Mean = (5*15 + 10*20) / 15 = (75 + 200) / 15 = 275 / 15 = 18.33.
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