Question

the number of observations in a group is 40. the average of the first 10 members is 4.5 and the average of the remaining 30 members is 3.5. the average of the whole group is

Answer 1

Total observations = 40
Average of First 10 observations = 4.5
Average of Remaining 30 observations = 3.5

Average of Total observations = (Sum of 10 members + Sum of Remaining 30 members ) / Total observations
Sum of First 10 members = 4.5 x 10 = 45
Sum of Remaining 30 members = 3.5 x 30 = 105

Hence, Average of Total observations = (45 + 105) / 40
= 150 / 40
Average of Total observations = 3. 75

Answer 2

Answer:

this is the correct Ans