Question

12. the time to order and deliver a pizza is 48 min. A new system was implemented that will hopefully reduce to time to serve a pizza to costumers. write the null and alternative hypotheses.

13. for the hypothesis of problem 12 the null hypothesis is rejected. state the conclusion of the hypothesis test.

14. The typical American spends 154.8 min a day, a survey of 30 internet users result in a mean time of 128.7 min, and a standard deviation of 46.5 min watching tv. conduct the appropriate test to determine if internet users spend less time watching tv at the alpha=0.05 level of significance. 14b. true or false. in step 4 of the hypotheses test, the correct conclusion is to fail to reject the null hypothesis.

Answer 1

12)

Below are the null and alternative Hypothesis,
Null Hypothesis, H0: μ = 48
Alternative Hypothesis, Ha: μ < 48

13)

There is sufficient evidence to conclude that A new system was implemented that will hopefully reduce to time to serve a pizza to costumers

14)

Below are the null and alternative Hypothesis,
Null Hypothesis, H0: μ = 154.8
Alternative Hypothesis, Ha: μ < 154.8

Rejection Region
This is left tailed test, for α = 0.05 and df = 29
Critical value of t is -1.699.
Hence reject H0 if t < -1.699

Test statistic,
t = (xbar - mu)/(s/sqrt(n))
t = (128.7 - 154.8)/(46.5/sqrt(30))
t = -3.074

P-value Approach
P-value = 0.0023
As P-value < 0.05, reject the null hypothesis.

Answer is false