document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1031560>Question 1031560</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Let x be the number of courses for which a randomly selected student at a certain university is registered. The probability distribution of x appears in the following table.<BR>\n" );
document.write( "x	1	2	3	4	5	6	7<BR>\n" );
document.write( "p(x)	0.02	0.03	0.09	0.25	0.39	0.17	0.05<BR>\n" );
document.write( "It can be easily verified that the mean value of random variable x = 4.67 and standard deviation of random variable x = 1.21.\r<BR>\n" );
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document.write( "(a) Because 4.67-1.21 = 3.46, the x values 1, 2, and 3 are more than 1 standard deviation below the mean. What is the probability that x is more than 1 standard deviation below its mean?<BR>\n" );
document.write( "P(x <4.67-1.21 ) =  0.000054<BR>\n" );
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document.write( "its incorrect but what i did was multiply the probabilities of the corresponding x values that was said to be more than one deviation<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #646237 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=646237\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <font face=\"Times New Roman\" size=\"+2\">\r<BR>\n" );
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document.write( "Your error was in multiplying the probabilities.  You need to add them.  The probability of 1, 2, or 3 is 0.14\r<BR>\n" );
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document.write( "John<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\LARGE e^{i\pi}\ +\ 1\ =\ 0\"><BR>\n" );
document.write( "My calculator said it, I believe it, that settles it\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/rendertex.cgi?\Large \ \\r\"> </SPAN>\n" );
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