document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1108219>Question 1108219</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Suppose z is a standard normal random variable. Find the value of z subscript italic alpha divided by 2 end subscript such that P left parenthesis minus z subscript alpha divided by 2 end subscript less than z less than space z subscript italic alpha divided by 2 end subscript right parenthesis equal .80 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #723243 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=723243\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> wow, you said a mouthful.\r<BR>\n" );
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document.write( "i think what you're looking for is the interval between the two end points, where the area in between is .8.\r<BR>\n" );
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document.write( ".8 in between means .2 outside which is divided by 2 to get .10 on each end.\r<BR>\n" );
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document.write( ".10 would be your alpha / 2.\r<BR>\n" );
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document.write( "to find the area with .8 in between, you would find the z-score for an area of.9 to the left of it and the z-score for an area of .1 to the left of it.\r<BR>\n" );
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document.write( "the area between the z-scores would be the area in between.\r<BR>\n" );
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document.write( "the z-score with an area to the left of it equal to .9 would be z = 1.281551567.\r<BR>\n" );
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document.write( "the z-score with an area to the left of it it equal to .1 would be z = -1.281551567.\r<BR>\n" );
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document.write( "the area in between is .8.\r<BR>\n" );
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document.write( "a picture of what what would look like is shown below.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" src = \"http://theo.x10hosting.com/2018/020101.jpg\" alt=\"$$$\" >\r<BR>\n" );
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document.write( "i'm assuming you are able to find the area to the left of a z-score and to find the z-score with a specified area to the left of it.\r<BR>\n" );
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document.write( "if you need help with that, let me know and i'll give you some more detailed instructions.\r<BR>\n" );
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document.write( "the calculator with the picture can also be used, but it will spoil you.\r<BR>\n" );
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document.write( "bet you learn how to do it the hard way first, so you have that up your sleeve in case you need it.\r<BR>\n" );
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document.write( "here's the link to the online calculator i used.\r<BR>\n" );
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document.write( "<a  rel=nofollow HREF= \"http://davidmlane.com/hyperstat/z_table.html\" target = \"_blank\">http://davidmlane.com/hyperstat/z_table.html</a>\r<BR>\n" );
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document.write( "here's a link to a table if you want to use that.\r<BR>\n" );
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document.write( "<a  rel=nofollow HREF= \"http://www.stat.ufl.edu/~athienit/Tables/Ztable.pdf\" target = \"_blank\">http://www.stat.ufl.edu/~athienit/Tables/Ztable.pdf</a>\r<BR>\n" );
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document.write( "let me know if this is what you wanted and, if not, what you might have been looking for that is not what i provided.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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