SOLUTION: 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 t
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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. Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! 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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Ho: p >= 0.45 (manager's claim)
Ha: p < 0.45
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sample proportion: 150/400 = 0.375
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test stat: z(0.375) = (0.375-0.45)/sqrt[0.45*0.55/400]
= -3.015
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Critical Value for left-tail test with alpha=3%
is z = invNorm(0.03) = -1.8808
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Conclusion:
Since the test statistic is in the reject interval
reject Ho, which is the manager's claim.
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Cheers,
Stan H.
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