If the population deviation is known and we wish to estimate the population mean with 95% confidence, which of the following would be the appropriate critical z-value to use?
A) 1.28
B) 1.645
C) 1.96
D) 2.33

Question

If the population deviation  is known and we wish to estimate the population mean  with 95% confidence, which of the following would be the appropriate critical z-value to use?
A) 1.28 
B) 1.645 
C) 1.96 
D) 2.33

Quizplus · Accepted Answer

To estimate the population mean with 95% confidence, we need to use the 95% confidence interval, which corresponds to a critical value of 1.96 for a normal distribution. This is because 95% of the area under a normal curve falls within 1.96 standard deviations of the mean. Therefore, choice C, with a critical value of 1.96, is the appropriate answer.

If the Population Deviation Is Known and We Wish