The following data represent the muzzle velocity (in feet per second) of shells

Question

The following data represent the muzzle velocity (in feet per second) of shells fired from a 155-mm gun. For each shell, two measurements of the velocity were recorded using two different measuring devices, resulting in the following data.

Observation A B

1 791.2 793.1

2 791.7 798.6

3 791.1 791.7

4 793.8 789.0

5 791.3 787.1

6 794.6 793.9

(a) Why are these matched-pairs data?

A. All the measurements came from rounds fired from the same gun.

B. The same round was fired in every trial.

C. The measurements (A and B) are taken by the same instrument.

D. Two measurements (A and B) are taken on the same round.

-reject or do not reject???

C. Construct a 99% confidence interval about the population mean difference. The confidence interval is (__, __) Round to three decimal places as needed. D.

Choose the statement that best agrees with your interpretation of your results.

A. I am 18% confident that the mean difference in the measurement is 0.01.

B. I am 1% confident that the mean difference in the measurement is lies in the interval found above.

C. I am 99% % confident that the mean difference in the measurement is lies in the interval found above.

D. I am 18% confident that that the mean difference in the measurement is 0.

Explanation / Answer

(a) D. Two measurements (A and B) are taken on the same round.

(b)

n1 = n2 = n = 6

d-bar = 0.05

s of d-bar = 4.3066

% = 99

Degrees of freedom = n - 1 = 5

SE = s/n = 1.758162088

t- score = 4.032142983

Width of the confidence interval = t * SE = 7.089160926

Lower limit of the confidence interval = d-bar - width = -7.039160926

Upper limit of the confidence interval = d-bar + width = 7.139160926

The 99% confidence interval is [-7.039, 7.139]

(c) C. I am 99% % confident that the mean difference in the measurement is lies in the interval found above.

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

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