SOLUTION: Please Help. . A researcher claims that the average age of people who buy lottery tickets is 63. A sample of 30 is selected and their ages are recorded as shown below. The standard

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Question 495147: Please Help. . A researcher claims that the average age of people who buy lottery tickets is 63. A sample of 30 is selected and their ages are recorded as shown below. The standard deviation is 5. At  = 0.05 is there enough evidence to reject the researcher�s claim? Show all work.

65 63 46 52 47 80 72 56 66 56
80 60 70 65 70 61 65 71 70 74
79 75 34 49 62 68 73 67 69 60

Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
A researcher claims that the average age of people who buy lottery tickets is 63. A sample of 30 is selected and their ages are recorded as shown below. The standard deviation is 5. At  = 0.05 is there enough evidence to reject the researcher�s claim? Show all work.
65 63 46 52 47 80 72 56 66 56
80 60 70 65 70 61 65 71 70 74
79 75 34 49 62 68 73 67 69 60
sample mean = 64.17 ; stand dev. = 10.78
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Ho: u = 63 (claim)
Ha: u is not equal to 63
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Critical value for 2-tail test with alpha = 5% = +-1.96
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Test statistic: z(64.17) = (64.17-63)/10.78 = 0.1085
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Conclusion: Since the Ts is not in the reject region,
fail to reject Ho. The test results support the claim.
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Cheers,
Stan H.
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