document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=189125>Question 189125</A>: <I><SPAN STYLE=\"word-break: break-all;\"> ``A coin was flipped 60 times and came up heads 38 times. \r<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( "(b) Calculate a p-value and interpret it.<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #141858 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=141858\">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( "(a) At the .10 level of significance, is the coin biased toward heads? Show your decision rule and calculations. <BR>\n" );
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document.write( "Ho: p = 1/2<BR>\n" );
document.write( "Ho: p > 1/2<BR>\n" );
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document.write( "sample proportion: 38/60 = 0.6333<BR>\n" );
document.write( "test statistic: z(0.6333) = (0.6333-0.5)/sqrt[(.5*.5/60] = 2.0656<BR>\n" );
document.write( "(b) Calculate a p-value and interpret it.<BR>\n" );
document.write( "p-value = P(z > 2.0656) = 0.0194<BR>\n" );
document.write( "This means the probability of a test providing stronger evidence<BR>\n" );
document.write( "for rejecting Ho is 1.094%<BR>\n" );
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document.write( "Conclusion: Since the p-value is less than alpha = 10%, reject Ho.<BR>\n" );
document.write( "The coin is biased toward heads.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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