Records of 40 used passenger cars and 40 used pickup trucks (none used commercially) were randomly selected to investigate whether there was any difference in the mean time in years that they were kept by the original owner before being sold. For cars the mean was 5.3 years with standard deviation 2.2 years. For pickup trucks the mean was 7.1 years with standard deviation 3.0 years. Test using the 1% level of significance. H0: ______ Ha: ____ In words, define the random variable. The distribution to use for the test is _____________. Calculate the test statistic using your data. Draw a graph and label it appropriately. Calculate the p-value. Do you reject or not reject the null hypothesis? Why? Write a clear conclusion using a complete sentence.
Added by Julian L.
Step 1
H0: μ1 = μ2 where μ1 is the mean time for passenger cars and μ2 is the mean time for pickup trucks. Show more…
Show all steps
Close
Your feedback will help us improve your experience
Sri K and 71 other Intro Stats / AP Statistics educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
Records of 40 used passenger cars and 40 used pickup trucks (none used commercially) were randomly selected to investigate whether there was any difference in the mean time in years that they were kept by the original owner before being sold. For cars the mean was 5.3 years with standard deviation 2.2 years. For pickup trucks the mean was 7.1 years with standard deviation 3.0 years. a. Construct the $95 \%$ confidence interval for the difference in the means based on these data. b. Test the hypothesis that there is a difference in the means against the null hypothesis that there is no difference. Use the $1 \%$ level of significance. c. Compute the observed significance of the test in part (b).
Two-Sample Problems
Comparison of Two Population Means: Large, Independent Samples
For each of the following questions, make sure you set up the null and alternative hypotheses, use both p-value and critical value method, and state your conclusion. If an alpha level is not explicitly mentioned in a problem, you may assume alpha = 0.05. 1. Records of 40 used passenger cars and 40 used pickup trucks (none used commercially) were randomly selected to investigate whether there was any difference in the mean time in years that they were kept by the original owner before being sold. For cars the mean was 5.3 years with standard deviation 2.2 years. For pickup trucks the mean was 7.1 years with standard deviation 3.0 years. Test the hypothesis that there is a difference in the means against the null hypothesis that there is no difference. Use the 1% level of significance.
Kari H.
(a) identify the claim and state $H_{0}$ and $H_{a},(b)$ find the critical value and identify the rejection region, $(c)$ find the test statistic $F,(d)$ decide whether to reject or fail to reject the null hypothesis, and (e) interpret the decision in the context of the original claim. Assume the samples are random and independent, the populations are normally distributed, and the population variances are equal. If convenient, use technology. The table shows the costs per mile (in cents) for a sample of automobiles. At $\alpha=0.01,$ can you conclude that at least one mean cost per mile is different from the others? (Adapted from American Automobile Association) $$\begin{array}{|c|c|c|c|c|}\hline \text { Small sedan } & \text { Medium sedan } & \text { Large sedan } & \text { SUV 4WD } & \text { Minivan } \\\hline 43 & 67 & 64 & 87 & 66 \\41 & 49 & 73 & 66 & 76 \\49 & 63 & 83 & 75 & 59 \\ 54 & 59 & 75 & 78 & 51 \\46 & 64 & 80 & & 70 \\& 52 & 72 & & \\\hline\end{array}$$
Chi-Square Tests and the F-Distribution
Analysis of Variance
Recommended Textbooks
Elementary Statistics a Step by Step Approach
The Practice of Statistics for AP
Introductory Statistics
Transcript
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD