document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1150738>Question 1150738</A>: <I><SPAN STYLE=\"word-break: break-all;\"> If X is normally distributed on (5,4) then what is the probability that<BR>\n" );
document.write( "8 < Y < 13 where Y = 2X + 1? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #772701 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=772701\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The mean is 2(mean of x)+1 or 11<BR>\n" );
document.write( "the variance is the square of the coefficient or 4 times the variance of the original.<BR>\n" );
document.write( "The sd of the original was 4, so its variance was 16 and the new variance is 64 with a sd of 8<BR>\n" );
document.write( "y is distributed normally with mean of 11 and sd of 8.\r<BR>\n" );
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document.write( "z=(x-mean)/sd<BR>\n" );
document.write( "so z for the low end is (8-11)/8 or -3/8<BR>\n" );
document.write( "and for the high end is (13-11)/8 or +1/4<BR>\n" );
document.write( "for z to be between these two values gives a probability of 0.2449\r<BR>\n" );
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