The police department is concerned about the ability of officers to identify dru

Question

The police department is concerned about the ability of officers to identify drunk drivers on the road. Before instituting a new training program they take a sample of 28 arrests and record the level of alcohol in the blood at the time of the arrest. The sample generated an average level of alcohol in the blood of 150.5 and standard deviation of 45.3. Assume that the level of alcohol in the blood is normally distributed. Find an 80% confidence interval for the average alcohol level in the blood at the time of arrest.

In finding an 80 percent confidence interval for the average alcohol level, the correct t-value to use in the formula is:

a. 1.057

b. 1.314

c. 1.703

d. 2.052

e. 2.291

Explanation / Answer

1 - 0.8 = 0.2

1 - 0.2 / 2 = 0.9

t0.9,27 = 1.314

So, the correct option is Option-B) 1.314

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.