document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=928128>Question 928128</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A local retailer claims that the mean waiting time is less than 8 minutes. A random sample of 20 waiting times has a sample mean of 6.4 minutes with a sample standard deviation of 2.1 minutes. A a=0.01 test the retailer's claim. The null hypothesis is mu=8 mins.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #563487 by </B><A HREF=/tutors/aboutme.mpl?userid=ewatrrr><B>ewatrrr(24785)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ewatrrr><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/cgi-bin/show-face.mpl?user=ewatrrr><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=563487\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Ho: u = 8min <BR>\n" );
document.write( "Ha: u < 8min (claim)<BR>\n" );
document.write( ".......<BR>\n" );
document.write( "sample of 20: mean of 6.4 minutes with a sample standard deviation of 2.1 minutes. <BR>\n" );
document.write( "t(6.4) = -1.6/(2.1/sqrt(20)) = -3.407<BR>\n" );
document.write( "p-value = tcdf(-100, -3.407, 19) = .0015<BR>\n" );
document.write( ".......<BR>\n" );
document.write( "confidence level .01<BR>\n" );
document.write( ".0015< .01<BR>\n" );
document.write( "Test results rejects Ho and supports retailer's claim<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );