A Mail-Order Business Prides Itself in Its Ability to Fill $\alpha$

question 130

Multiple Choice

A mail-order business prides itself in its ability to fill customers' orders in less than six calendar days,on average.Periodically,the operations manager selects a random sample of customer orders and determines the number of days required to fill the orders.On one occasion when a sample of 39 orders was selected,the average number of days was 6.65 with a sample standard deviation of 1.5 days.What is the critical value for $\alpha$ = .10 to test the hypotheses.

• A)-1.28
• B)-1.96
• C)-2.33
• D)1.28
• E)1.96

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Definitions:

Hypothesis Testing

A statistical method to decide whether to accept or reject a hypothesis based on sample data.

Significance Level

The probability of rejecting the null hypothesis in a statistical test when it is true. Often denoted by alpha, it's a measure of the risk of a Type I error.

Confidence Coefficient

The probability level associated with a confidence interval, often expressed as a percentage, indicating the degree of certainty in the estimate.

Type I Error

A statistical error that occurs when a true null hypothesis is incorrectly rejected.