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![In many problems we interested in estimation of the population mean. Let X1,., X10
be a random sample from a population with mean µ and variance o?. Consider the
following estimators for estimating µ:
X1+ X2 + · …+X10
3X1 – 2X5 + 3X10
10
2
Compute the variance of the estimators.
A. V[Ô¡] = o²/10, v[Ô2] = 11o²/2 B. V[Ô¡] = 30²/2, V(Ô2] = 30²/7
C. V[Ô‚] = o²/10, V(Ô¿] = 80²/2 D. V[Ô‚] = o²/100, V[Ô¿] = 4o²/2
E. none of the prcceding
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