A Random Sample of Size N Has Been Selected from a Normally

question 168

Multiple Choice

A random sample of size n has been selected from a normally distributed population whose standard deviation is . In hypothesis testing for the population mean, the t-test should be used instead of the z-test if:

• A) n > 30 and σ is unknown
• B) n < 30 and σ is unknown
• C) n < 30 and σ is known
• D) n < 30 and β is known
• E) n > 30 and σ is unknown and n < 30 and σ is known

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