document.write( "Question 129973: I already submitted this question. The missing data is Apha=.05. Please help me. I am totally lost and need your help. Thank you again\r
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\n" ); document.write( "\n" ); document.write( "1. The EPA is concerned about the quality of drinking water served on airline flights. A sample of 158 flights yielded poor quality water on 20 flights. At alpha=.05, does this indicate that more than 10% of flights have poor-quality water?\r
\n" ); document.write( "\n" ); document.write( "2. According to the sample, 12.66% (20/158) of the flights served poor-quality water. Can you simply report to the EPA that more than 10% of all airline flights serve poor-quality water? Why or why not?\r
\n" ); document.write( "\n" ); document.write( "3. If an error occurred, what type of error was it?
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Algebra.Com's Answer #94957 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
1. The EPA is concerned about the quality of drinking water served on airline flights.
\n" ); document.write( " A sample of 158 flights yielded poor quality water on 20 flights. At alpha=.05, does this indicate that more than 10% of flights have poor-quality water?
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\n" ); document.write( "Ho: p = 0.10
\n" ); document.write( "Ha: p > 0.10 (right-tail test with alpha = 5%)
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\n" ); document.write( "Critical value = 1.645
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\n" ); document.write( "p-hat = 20/158 = 0.1266
\n" ); document.write( "Test Statistic:
\n" ); document.write( "z(0.1266) = (0.1266-0.10)/sqrt(0.1*0.9/158)= 46.69777...
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\n" ); document.write( "Since the test statistic is greater than the critical value
\n" ); document.write( "reject Ho. There is strong statistical evidence that the
\n" ); document.write( "proportion pf poor quality is not 10% \r
\n" ); document.write( "\n" ); document.write( "2. According to the sample, 12.66% (20/158) of the flights served poor-quality water. Can you simply report to the EPA that more than 10% of all airline flights serve poor-quality water? Why or why not?
\n" ); document.write( "Since this is a test of Ho that p = 10% you can only report that the
\n" ); document.write( "test shows significant statistical evidence that the proportion is not 10%.
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\n" ); document.write( "3. If an error occurred, what type of error was it?
\n" ); document.write( "Type I; rejecting Ho when in fact it is true.
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.\r
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