In order to test whether camshafts are being manufactured to specification a sample of n =...

90.2K

Verified Solution

Question

Statistics

In order to test whether camshafts are being manufactured tospecification a sample of n = 50 camshafts are selected at random.The average value of the sample is calculated to be 4.38 mm and thedepths of the camshafts in the sample vary by a standard deviationof s = 0.42 mm.
Test the hypotheses selected previously, by filling in theblanks in the following:
An estimate of the population mean is .
The standard error is .
The distribution isÂ Â (examples: normal / t12 /chisquare4 / F5,6).
The test statistic has value TS=Â Â .
Testing at significance level Î± = 0.01, the rejection regionis:
less thanÂ Â and greater thanÂ Â (2 decplaces).
Since the test statisticÂ Â (is in/is not in) therejection region, there (is evidence/is no evidence) toreject the null hypothesis, H ₀.
ThereÂ Â (is sufficient/is insufficient) evidenceto suggest that the average hardness depth, Î¼, is different to 4.5mm.
Were any assumptions required in order for thisinference to be valid?
a: No - the Central Limit Theorem applies, which states thesampling distribution is normal for any populationdistribution.
b: Yes - the population distribution must be normallydistributed.
Insert your choice (a or b): .

Answer & Explanation Solved by verified expert

4.2 Ratings (565 Votes)

Since the sample size 30 we can use z score even though the population standard deviation is not known An estimate of the population mean is the sample See Answer

Get Answers to Unlimited Questions

Join us to gain access to millions of questions and expert answers. Enjoy exclusive benefits tailored just for you!

Membership Benefits:

Unlimited Question Access with detailed Answers
Zin AI - 3 Million Words
10 Dall-E 3 Images
20 Plot Generations
Conversation with Dialogue Memory
No Ads, Ever!
Access to Our Best AI Platform: Flex AI - Your personal assistant for all your inquiries!

Become a Member