document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=77800>Question 77800</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am having a very hard time with this problem! Please help!\r<BR>\n" );
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document.write( "The time a group of high school students arrive home from school each day was found to be normally distributed. The mean time was 3:15 PM and the times had a standard deviation of 15 minutes. What is the probability that a student chosed at random arrives home from school before 2:30 PM? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #55785 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=55785\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The mean time was 3:15 PM and the times had a standard deviation of 15 minutes. What is the probability that a student chosen at random arrives home from school before 2:30 PM?<BR>\n" );
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document.write( "3:15 corresponds to zero on the z-distribution.<BR>\n" );
document.write( "If the standard deviation is 15 minutes, 2:30<BR>\n" );
document.write( "would be three standard deviation to the left<BR>\n" );
document.write( "of the mean.<BR>\n" );
document.write( "The probability that z<-3 = 0.0013499<BR>\n" );
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document.write( "Let me know if you do not understand this and<BR>\n" );
document.write( "what it is you do not understand.<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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