document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=460767>Question 460767</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A doctor says that less than 25% of US adults chew tobacco. In a random sample of 170 US adults, 18.5% say they chew tobacco. At alpha = .05, is there enough evidence to reject the doctor's claim? \r<BR>\n" );
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document.write( "Since I don't have a standard deviation, do I use t-distribution? Or do I use binomial distribution and find it by square root of npq? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #316053 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=316053\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> A doctor says that less than 25% of US adults chew tobacco. <BR>\n" );
document.write( "In a random sample of 170 US adults, 18.5% say they chew tobacco. <BR>\n" );
document.write( "At alpha = .05, is there enough evidence to reject the doctor's claim? <BR>\n" );
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document.write( "Since I don't have a standard deviation, do I use t-distribution? Or do I use --binomial distribution and find it by square root of npq?<BR>\n" );
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document.write( "It is a proportion test so you use the z-distribution.<BR>\n" );
document.write( "The standard deviation is sqrt[pq/n].  You have all <BR>\n" );
document.write( "the information you need.<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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