For two data sets, each of size 5, the variances are given to be 4 and 5 and the corresponding means are given to be 2 and 4, respectively. The variance of the combined data set is
As we learnt in
ARITHMETIC Mean -
The arithmetic mean is defined as the sum of items divided by the number of items.
-
and
Variance -
In case of discrete data
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Given v1=4 and v2=5
and
Variance =
= 14.5-9=5.5=
Option 1)
This is incorrect option
Option 2)
This is correct option
Option 3)
This is incorrect option
Option 4)
This is incorrect option
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