The mean of two samples of the sizes 250 and 320 were found to be 20, – McqOptions

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1.	The mean of two samples of the sizes 250 and 320 were found to be 20,12 respectively. Their standard deviations were 2 & 5, respectively. Find the variance of combined sample of size 650.
A.	10.23
B.	32.5
C.	65
D.	26.17
Answer» E.

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