document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=898708>Question 898708</A>: <I><SPAN STYLE=\"word-break: break-all;\"> please help me solve this probability problem.\r<BR>\n" );
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document.write( "1. Given a normal distribution of values for which the mean is 75 and the standard deviation is 5.<BR>\n" );
document.write( "A. Find the probability that a value between 60 and 80,inclusive.<BR>\n" );
document.write( "B.Find the probability that a value is greater than or equal to 64.<BR>\n" );
document.write( "C. Find the probability that a value is less than 78.<BR>\n" );
document.write( "D.Find the 80th percentile for this distribution. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #544976 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=544976\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 1. Given a normal distribution of values for which the mean is 75 and the standard deviation is 5.<BR>\n" );
document.write( " A. Find the probability that a value between 60 and 80,inclusive.<BR>\n" );
document.write( "z(60) = (60-75)/5 = -3<BR>\n" );
document.write( "z(80) = (80-75)/5 = 1<BR>\n" );
document.write( "----<BR>\n" );
document.write( "P(60<= x <=80) = P(=3<= z <=1) = normalcdf(-3,1) = 0.0400<BR>\n" );
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document.write( "B.Find the probability that a value is greater than or equal to 64.<BR>\n" );
document.write( "z(64) = (64-75)/5 = -2.2<BR>\n" );
document.write( "P(x >= 64) = p(z >= =2.2) = normalcdf(-2.2,100) = 0.9860<BR>\n" );
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document.write( " C. Find the probability that a value is less than 78.<BR>\n" );
document.write( "z(78) = (78-75)/5 = 1<BR>\n" );
document.write( "P(z < 78) = P(z < 1) = normalcdf(-100,1) = 0.8413<BR>\n" );
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document.write( " D.Find the 80th percentile for this distribution.<BR>\n" );
document.write( "invNorm(0.8) = 0.8416<BR>\n" );
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document.write( "Find the corresponding value::<BR>\n" );
document.write( "x = 0.8416*5+75 = 79.21<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( "============================ </SPAN>\n" );
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