document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1191285>Question 1191285</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The time taken for a student to complete an exam is normally distributed with a mean of 40 minutes and a standard deviation of 5.5 minutes. \r<BR>\n" );
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document.write( "The probability a student takes between k and 48 minutes is 0.4. What is the value of k? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #823102 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=823102\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> z=(x-mean)/sd<BR>\n" );
document.write( "z=(48-40)/5.5<BR>\n" );
document.write( "=1.454<BR>\n" );
document.write( "probability <48 minutes is 0.9271<BR>\n" );
document.write( "use the table and find that for probability 0.5271 being less than a certain number of minutes, z=0.068<BR>\n" );
document.write( ".<BR>\n" );
document.write( "The probability that z is between 0.068 and 1.454 is 0.40<BR>\n" );
document.write( "0.064=(k-40)/5.5<BR>\n" );
document.write( "0.352=(x-40)<BR>\n" );
document.write( "k=40.352 minutes </SPAN>\n" );
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