document.write( "Question 264516: A new car is designed to run a mean of at least 50 000 kilometres before its first tune-up. Tests with 30 cars show a sample mean of 49 500 kilometres and a sample standard deviation of 1000 kilometres.
\n" ); document.write( "a.
\n" ); document.write( "Develop the null and alternative hypotheses most appropriate for testing the claim that the new car can run at least 50 000 kilometres before its first tune-up.
\n" ); document.write( "b.
\n" ); document.write( "Using a .05 level of significance, test whether or not there is sufficient evidence to reject the claim of a mean of at least 50 000 kilometres.
\n" ); document.write( "c.
\n" ); document.write( "What is the p-value.
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Algebra.Com's Answer #194752 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
A new car is designed to run a mean of at least 50 000 kilometres before its first tune-up. Tests with 30 cars show a sample mean of 49 500 kilometres and a sample standard deviation of 1000 kilometres.
\n" ); document.write( "a.
\n" ); document.write( "Develop the null and alternative hypotheses most appropriate for testing the claim that the new car can run at least 50 000 kilometres before its first tune-up.
\n" ); document.write( "Ho: u >= 50.000
\n" ); document.write( "Ha: u < 50,000
\n" ); document.write( "b.
\n" ); document.write( "Using a .05 level of significance, test whether or not there is sufficient evidence to reject the claim of a mean of at least 50 000 kilometres.
\n" ); document.write( "test statistic: t(49,5000) = (49500-50,000)/[1000/Sqrt(30)] = -2.7386...
\n" ); document.write( "critical value: invT(0.05,df=29) = -1.6991..
\n" ); document.write( "Conclusion: Since the ts is to the left of the cv, reject Ho.
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\n" ); document.write( "c.
\n" ); document.write( "What is the p-value.
\n" ); document.write( "p-value = P(t<-1.6991 when df = 29) = tcdf(-100,-2.7386,df=29) = 0.00522
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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