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Consider 10 observations x1, x2, , x10 such that i=110 (xi- )=2 and i=110 (xi- )2=40, where , are positive integers. Let the mean and the variance of the observations be 65 and 8425 respectively. Then is equal to :
(1) 2
(xi- )=2 xi-10 =2 x- = 15
= 65- 15=1
(xi- )2= (xi- x)2+10( x- )2=10 2+10( x- )2
40=10 8425+10 ( 65- )2
( 65- )2= 1625 =2 or 25
is a positive integer, =2 =2
Answer: (1)
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