document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=316275>Question 316275</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Trying to get my head around normal distribution, please help.\r<BR>\n" );
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document.write( "The time spent by students working on a project is a normal random variable with parameters m = 12 hours and s = 4 hours. Compute the probability that<BR>\n" );
document.write( "(a)    the amount of time spent on the project is less than 14 hours.<BR>\n" );
document.write( "(b)   the amount of time spent on the project is greater than 8 hours. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #226223 by </B><A HREF=/tutors/aboutme.mpl?userid=Fombitz><B>Fombitz(32388)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fombitz><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=Fombitz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=226223\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a) Find the z-score.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=z=%28x-mu%29%2Fsigma=%2814-12%29%2F4=0.5 ALIGN=MIDDLE  ALT=\"z=%28x-mu%29%2Fsigma=%2814-12%29%2F4=0.5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Find <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P%280.5%29 ALIGN=MIDDLE  ALT=\"P%280.5%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P%280.5%29=0.691462 ALIGN=MIDDLE  ALT=\"P%280.5%29=0.691462\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( ".<BR>\n" );
document.write( ".<BR>\n" );
document.write( ".<BR>\n" );
document.write( "b) Find the z-score.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=z=%28x-mu%29%2Fsigma=%288-12%29%2F4=0.5 ALIGN=MIDDLE  ALT=\"z=%28x-mu%29%2Fsigma=%288-12%29%2F4=0.5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Find <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P%28-1%29 ALIGN=MIDDLE  ALT=\"P%28-1%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P%28-1%29=0.158655 ALIGN=MIDDLE  ALT=\"P%28-1%29=0.158655\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "This is the probability that covers 8 hrs and less.<BR>\n" );
document.write( "You're looking for more than 8.<BR>\n" );
document.write( "P(x <= 8)+P(x > 8)=1<BR>\n" );
document.write( "P(x > 8)=1-P(x <= 8)<BR>\n" );
document.write( "P(x > 8)=1-0.159655<BR>\n" );
document.write( "P(x > 8)=0.841345<BR>\n" );
document.write( " </SPAN>\n" );
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