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A sample of 35 observations has the mean...

A sample of 35 observations has the means 80 and SD. As 4. A second sample of 65 observations from the same population has mean 70 and S.D.3. The S.D. of the combined sample is -

A

`5.85`

B

`5.58`

C

`34.2`

D

None of these

Text Solution

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The correct Answer is:
A
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