Question
upstudy study bank question image url

A manufacturer must test that his bolts are 2.00 cm long when they come off the assembly line. He must recalibrate his machines if the bolts are too
long or too short. After sampling 169 randomly selected bolts off the assembly line, he calculates the sample mean to be 2.05 cm . He knows that the
population standard deviation is 0.29 cm . Assuming a level of significance of 0.01 , is there sufficient evidence to show that the manufacturer needs
to recalibrate the machines?
Step 1 of 3: State the null and alternative hypotheses for the test. Fill in the blank below.

Ask by Chavez Reeves. in the United States
Dec 24,2024

Upstudy AI Solution

Tutor-Verified Answer

Answer

The hypotheses are:

Solution

Sign in to Unlock Answers for Free!

A Learning Platform Trusted by Millions of Real Students and Teachers.

star-icon Unlock

Answered by UpStudy AI and reviewed by a Professional Tutor

Bonus Knowledge

To test if the manufacturer needs to recalibrate the machines, we set up our hypotheses. The null hypothesis states that there is no need for recalibration and that the mean length of the bolts is indeed 2.00 cm. In contrast, the alternative hypothesis suggests that the average length differs from this target, indicating that recalibration is necessary. This can be formally stated as:
This sets the stage for us to conduct a two-tailed test to determine whether the bolts are significantly different from the required length.
Next, when taking samples for testing, it’s essential to ensure randomness. This means selecting bolts in a way that any bolt has an equal chance of being included in the sample. A common mistake is using a non-random sampling method, such as only picking from the first few bolts off the assembly line. This can lead to biased results and give an inaccurate representation of the population, potentially skewing the conclusions drawn from the hypothesis test. Remember, randomness is key!

Related Questions

Latest Statistics Questions

Try Premium now!
Try Premium and ask Thoth AI unlimited math questions now!
Maybe later Go Premium
Study can be a real struggle
Why not UpStudy it?
Select your plan below
Premium

You can enjoy

Start now
  • Step-by-step explanations
  • 24/7 expert live tutors
  • Unlimited number of questions
  • No interruptions
  • Full access to Answer and Solution
  • Full Access to PDF Chat, UpStudy Chat, Browsing Chat
Basic

Totally free but limited

  • Limited Solution
Welcome to UpStudy!
Please sign in to continue the Thoth AI Chat journey
Continue with Email
Or continue with
By clicking “Sign in”, you agree to our Terms of Use & Privacy Policy