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It is known that the population variance is 144. At 95% confidence, what sample size?a. 22.b. 23.c. 24.d. 25.e. none of the above.

User Lbrahim
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Answer:

(E) None of the above

Explanation:

The statistic provided is that of the population but the statistic you seek is that of the sample.

Looking at the statistic itself, Variance is the square of Standard Deviation or standard deviation is the square root of variance.

Hence you calculate the standard deviation of the population mean:

√144 = 12

The population standard deviation of/from the mean value is 12.

It could be possible to decipher the sample mean from population mean but not sample size.

So, you can't pick just any answer. Population size should be given first.

User Dori Naji
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