document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1043193>Question 1043193</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The life spans of a computer manufacturer’s hard drives are normally distributed, with a mean of 3 years 6 months and a standard deviation of 9 months. What is the probability of a randomly selected hard drive from the company lasting between 2 years 3 months and 3 years 3 months? Use the portion of the standard normal table below to help answer the question </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #658314 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=658314\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The life spans of a computer manufacturer’s hard drives are normally distributed, with a mean of 3 years 6 months and a standard deviation of 9 months. What is the probability of a randomly selected hard drive from the company lasting between 2 years 3 months and 3 years 3 months?<BR>\n" );
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document.write( "z(2.25) = (2.25-3.5)/(0.75) = -4/3 <BR>\n" );
document.write( "z(3.25) = (3.25-3.5)/(0.75) = -1/3<BR>\n" );
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document.write( "P(2.25< x <3.25) = P(-4/3< z < -1/3) = normalcdf(-4/3,-1/3) = 0.2782<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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