SOLUTION: In a certain manufacturing process, the diameter of holes drilled in a steel plate is a normally distributed random variable. The process standard deviation is known to be σ=

Algebra ->  Probability-and-statistics -> SOLUTION: In a certain manufacturing process, the diameter of holes drilled in a steel plate is a normally distributed random variable. The process standard deviation is known to be σ=      Log On


   

Question 336344: In a certain manufacturing process, the diameter of holes drilled in a steel plate is a normally
distributed random variable. The process standard deviation is known to be σ=0.005 cm.A sample
of 15 plates shows a mean hole diameter of 2.475 cm. Find the 95 percent confidence interval for μ.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
In a certain manufacturing process, the diameter of holes drilled in a steel plate is a normally distributed random variable.
The process standard deviation is known to be σ=0.005 cm.
A sample of 15 plates shows a mean hole diameter of 2.475 cm.
Find the 95 percent confidence interval for μ.
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x-bar = 2.475
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E = invT(0.025 with df = 14) = 0.0028
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95% CI: 2.475- 0.0028 < u < 2.475+ 0.0028
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(2.4722,2.4778)
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Cheers,
Stan H.