Question
In usual notations find combined standard deviation from the following informations:
$n_{1}=10, \bar{x}_{1}=16, S_{1}=2 ; n_{2}=60, \bar{x}_{2}=$
$22, s_{2}=2.5$
$n_{1}=10, \bar{x}_{1}=16, S_{1}=2 ; n_{2}=60, \bar{x}_{2}=$
$22, s_{2}=2.5$
✓
Answer
$\bar{x}_{c}=21.14, s_{c}=3.22$
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