document.write( "Question 285330: A department store manager claims that at least 45% of persons who visited this store make a purchase. In a sample of 400 persons who visited the store 150 made a purchase. Test the manager’s claim at the 3% significance level. \n" ); document.write( "
Algebra.Com's Answer #206848 by stanbon(75887)\"\" \"About 
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A department store manager claims that at least 45% of persons who visited this store make a purchase. In a sample of 400 persons who visited the store 150 made a purchase. Test the manager’s claim at the 3% significance level.
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\n" ); document.write( "Ho: p >= 0.45 (manager's claim)
\n" ); document.write( "Ha: p < 0.45
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\n" ); document.write( "sample proportion: 150/400 = 0.375
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\n" ); document.write( "test stat: z(0.375) = (0.375-0.45)/sqrt[0.45*0.55/400]
\n" ); document.write( "= -3.015
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\n" ); document.write( "Critical Value for left-tail test with alpha=3%
\n" ); document.write( "is z = invNorm(0.03) = -1.8808
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\n" ); document.write( "Conclusion:
\n" ); document.write( "Since the test statistic is in the reject interval
\n" ); document.write( "reject Ho, which is the manager's claim.
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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