document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1131823>Question 1131823</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Help needed please.\r<BR>\n" );
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document.write( "The mean of a product is 15 days, with a standard deviation of 3 days. With normal distribution, what is the probability that measured shelf<BR>\n" );
document.write( "life is more than 12 days?\r<BR>\n" );
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document.write( "I believe I am supposed to find the Z score, which I found to be -1, but not certain, and it doesn't seem right.\r<BR>\n" );
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document.write( "Can someone please guide me through how to figure this out?\r<BR>\n" );
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document.write( "Thanks!\r<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 #748502 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><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=748502\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font color=\"black\" face=\"times\" size=\"3\"><BR>\n" );
document.write( "You have the proper z score. Now use that value to find the area under the normal curve that is to the left of z = -1.00\r<BR>\n" );
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document.write( "You can use a table such as <a  rel=nofollow HREF= \"http://users.stat.ufl.edu/~athienit/Tables/Ztable.pdf\">this one</a> (the back of your textbook should have something similar)<BR>\n" );
document.write( "Locate the row that starts with -1.0 and the column that has 0.00 at the top. At the intersection of this row and column is the value 0.1587\r<BR>\n" );
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document.write( "So, the area under the curve to the left of z = -1 is 0.1587 approximately<BR>\n" );
document.write( "The area to the right of the z score is going to be roughly 1-0.1587 = 0.8413\r<BR>\n" );
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document.write( "The approximate final answer is <font color=red>0.8413</font> which is about a 84.13% chance<BR>\n" );
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