document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=795308>Question 795308</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am having so much difficulty figuring these out.<BR>\n" );
document.write( "Suppose the replacement times for washing Machines are normally distributed with a mean of 9.3 years and a standard deviation of 1.1 years. Find the probability that 70 randomly selected washing Machines will have a mean replacement time less than 9.1 years. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #480920 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=480920\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Suppose the replacement times for washing Machines are normally distributed with a mean of 9.3 years and a standard deviation of 1.1 years. Find the probability that 70 randomly selected washing Machines will have a mean replacement time less than 9.1 years.<BR>\n" );
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document.write( "z(9.1) = (9.1-9.3)/(1.1/sqrt(70)) = -0.2/(0.1315) = -1.5209<BR>\n" );
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document.write( "P(x-bar<9.1) = P(z<-1.5209) = normalcdf(-100,-1.5209)= 0.0641<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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