document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=135217>Question 135217</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A coin was flipped 60 times and came up heads 38 times.  (a) at the .10 level of significance, is the coin biased toward heards?  Show your decision rule and calculations. (b) Calculate a p-value and interpret it. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #99038 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=99038\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A coin was flipped 60 times and came up heads 38 times.<BR>\n" );
document.write( "p-hat = 38/60 = 19/30<BR>\n" );
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document.write( "(a) at the .10 level of significance, is the coin biased toward heads?  Show your decision rule and calculations.<BR>\n" );
document.write( "Ho: p= 1/2<BR>\n" );
document.write( "Ha: p> 1/2<BR>\n" );
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document.write( "Critical value of one-tail z-test with alpha = 5%: z = 1.645<BR>\n" );
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document.write( "Test statistic: z(19/30) = ((19/30)-(1/2))/sqrt[(0.5*0.5)/60] = 0.1333/0.0645<BR>\n" );
document.write( "= 2.0651<BR>\n" );
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document.write( "Conclusion: Since test stat lies in the rejection interval, Reject Ho.<BR>\n" );
document.write( "The test provides statistical evidence the coin is biased toward heads.<BR>\n" );
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document.write( "(b) Calculate a p-value and interpret it.<BR>\n" );
document.write( "p-value = P(2.0651 < z < 10) = 0.0191<BR>\n" );
document.write( "That means there is only a 1.91% chance the statistical results could<BR>\n" );
document.write( "have provided stronger evidence for rejecting Ho.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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