Question

The mean of 19 observations is 40, three observations 31, 35 and 48 are deleted and one observation 68 is included. Then, find the mean of the final observations.

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Answer 1

Step-by-step explanation:

Let observations be:

X1,X2,..........x19

Mean= (X1+....X19)/19 = 40.

So, (X1+.....X19)= 40*19.

Three observations are deleted.

X1+....X16 = 40*19-(31+35+48)

one observation is added.

X1+....x17 = 40*19-(31+35+48)+68

New mean= (X1+....x17)/17

Answer 2

Answer:

41.88

Step-by-step explanation:

Find sum of all 19 observation

= 19 * 40 = 760

Sum of 16 entries after removing

31 , 35 and 48

= 760 - ( 31 + 35 + 48 ) = 644

Adding 68 sum of 17 observation

= 644 + 68 = 712

$so \: \: average = \frac{712}{17} = 41.88$