Question

To illustrate the effects of driving under the influence​ (DUI) of​ alcohol, a police officer brought a DUI simulator to a local high school. Student reaction time in an emergency was measured with unimpaired vision and also while wearing a pair of special goggles to simulate the effects of alcohol on vision. For a random sample of nine​ teenagers, the time​ (in seconds) required to bring the vehicle to a stop from a speed of 60 miles per hour was recorded. Complete parts​ (a) and​ (b).

​Note: A normal probability plot and boxplot of the data indicate that the differences are approximately normally distributed with no outliers.

Data table:

Subject	1	2	3	4	5	6	7	8	9
​Normal, Upper X Subscript iXi	4.49	4.34	4.58	4.56	4.31	4.80	4.59	5.00	4.79
​Impaired, Upper Y Subscript iYi	5.86	5.85	5.51	5.29	5.90	5.49	5.23	5.61	5.63

​(a) Whether the student had unimpaired vision or wore goggles first was randomly selected. Why is this a good idea in designing the​ experiment?

A. This is a good idea in designing the experiment because it controls for any​ "learning" that may occur in using the simulator.

B. This is a good idea in designing the experiment because the sample size is not large enough.

C. This is a good idea in designing the experiment because reaction times are different.

(b) Use a​ 95% confidence interval to test if there is a difference in braking time with impaired vision and normal vision where the differences are computed as​ "impaired minus​ normal."

The lower bound is ___

The upper bound is___

​(Round to the nearest thousandth as​ needed.)

State the appropriate conclusion. Choose the correct answer below.

a. There is insufficient evidence to conclude there is a difference in braking time with impaired vision and normal vision.

b. There is sufficient evidence to conclude there is a difference in braking time with impaired vision and normal vision.

Answer 1

a)

A. This is a good idea in designing the experiment because it controls for any​ "learning" that may occur in using the simulator.

b) lower bound - 0.6628

Upper bound - 1.2172

c) since the interval donot contain 0 then we can conclude that :

b. There is sufficient evidence to conclude there is a difference in braking time with impaired vision and normal vision