Question 134849
A manufacturer claims that at least 99% of all his products meet the minimum government standards. A survey of 500 products revealed ten did not meet the standard. 
Conduct the 5-step hypothesis test … and answer the following:
What is the null hypothesis?
Ho: p = 0.99
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What is the alternate hypothesis?
Ha: p > 0.99 (Claim)
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What is the critical value if a = .01?
z = 2.326
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What is the z-statistic? 
p-hat = 490/500 = 0.98
z(0.98) = (0.98-0.99)*[sqrt(0.99)*(0.01)/500] = -2.2473
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What is your decision ?? Do the products meet the government standards?
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This is a bit confusing.  The stated claim was that the company exceeded
the government standard; we tested that claim and the conclusion is a 
rejection of Ho. The test gives strong evidence that p is less than 99%.
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Now we are asked whether the product meets the government standard.  That requires the following testing:
Ho: p=0.99
Ha: p<0.99
This requires a left-tail test.
Critical value is -2.326
P-hat is still 0.98
Test statistic remains - 2.2473
Conclusion: Since test stat is in the rejection interval below
the critical value, reject Ho.
The product does not meet the government standard.
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Cheers,
Stan H.