25. The mean of 10 observations is 7 and mean of 15 observation is 12. – InterviewSolution

1.	25. The mean of 10 observations is 7 and mean of 15 observation is 12. Then the mean of allobservations-a)7b) 12c) 10d) 15
Answer» Sum of first set of observations = 107 = 70.Sum of second set of observations = 1512 = 180. Mean = (180+70)/(10+15)= 250/25= 10

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