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Hypothesis Testing & Confidence Interval

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Statistics Failure and reliability problem.

A tire supplier claims that the tread life of its tyres has a mean of 32000 miles. The buyer has doubts.
State the suitable null and alternative hypothesis to test this claim.
A testing agency randomly selects 25 vehicles. He puts the new tyres on the vehicle and runs the tyres to failure. If Mi is the mileage of the ith tyre,
â??Mi = 794,000 and
â??Mi^2 = 25,230,249,423
What is the sample mean of the mileage?
What is the sample variance of the mileage?
What is the standard error of the average mileage?
What is the 90% confidence interval for the mean mileage?
Test hypothesis at ? = 0.05

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A tire supplier claims that the tread life of its tyres has a mean of 32000 miles. The buyer has doubts.
State the suitable null and alternative hypothesis to test this claim.
The null hypothesis tested is
H0: Average mileage of tyres ≥ 32000 (µ ≥ 32000)
The alternative hypothesis is
H1: Average mileage of tyres < 32000 (µ < 32000)
A testing agency randomly selects 25 vehicles. He puts the new tyres on the vehicle and runs the tyres to failure. If Mi is the mileage of the ith tyre,
= 794,000 and
= 25,230,249,423
Answers
What is the sample mean of the mileage?
Sample mean, = 31760
What is the sample variance of the ...

Solution Summary

The solution provides step by step method for the calculation of testing of hypothesis and confidence interval. Formula for the calculation and Interpretations of the results are also included. Interactive excel sheet is included. The user can edit the inputs and obtain the complete results for a new set of data.

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