document.write( "Question 392762: A researcher predicts that listening to music while solving math problems will
\n" ); document.write( "make a particular brain area more active. To test this, a research participant has
\n" ); document.write( "her brain scanned while listening to music and solving math problems, and the
\n" ); document.write( "brain area of interest has a percentage signal change of 58. From many previous
\n" ); document.write( "studies with this same math problems procedure (but not listening to music), it is
\n" ); document.write( "known that the signal change in this brain area is normally distributed with a
\n" ); document.write( "mean of 35 and a standard deviation of 10. (a) Using the .01 level, what should
\n" ); document.write( "the researcher conclude? Solve this problem explicitly using all five steps of hypothesis
\n" ); document.write( "testing, and illustrate your answer with a sketch showing the comparison
\n" ); document.write( "distribution, the cutoff (or cutoffs), and the score of the sample on this distribution.
\n" ); document.write( "(b) Then explain your answer to someone who has never had a course in statistics
\n" ); document.write( "(but who is familiar with mean, standard deviation, and Z scores).
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Algebra.Com's Answer #278823 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
A researcher predicts that listening to music while solving math problems will
\n" ); document.write( "make a particular brain area more active. (that is the claim)
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\n" ); document.write( "To test this, a research participant has her brain scanned while listening to music and solving math problems, and the brain area of interest has a percentage signal change of 58. (that is the sample mean)
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\n" ); document.write( "From many previous studies with this same math problems procedure (but not listening to music), it is known that the signal change in this brain area is normally distributed with a mean of 35 and a standard deviation of 10.
\n" ); document.write( "(that is the population data)
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\n" ); document.write( "\n" ); document.write( "(a) Using the .01 level, what should the researcher conclude?
\n" ); document.write( "Solve this problem explicitly using all five steps of hypothesis
\n" ); document.write( "testing, and illustrate your answer with a sketch showing the comparison
\n" ); document.write( "distribution, the cutoff (or cutoffs), and the score of the sample on this distribution.
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\n" ); document.write( "Ho: u = 35
\n" ); document.write( "Ha: u > 35 (claim)
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\n" ); document.write( "z(58) = (58-35)/10 = 23/10 = 2.3
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\n" ); document.write( "The critical region for a right tail test with alpha = 1% is z>2.3263
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\n" ); document.write( "Conclusion: Since the test statistic is less than z = 2.3263, reject Ho.
\n" ); document.write( "The test results support the claim.
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\n" ); document.write( "Cautionary Note. Since the test statistic is barely in the reject interval
\n" ); document.write( "more testing is required.
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
\n" ); document.write( "(b) Then explain your answer to someone who has never had a course in statistics
\n" ); document.write( "(but who is familiar with mean, standard deviation, and Z scores).
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