document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1184198>Question 1184198</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A random variable X has the following probability function define as P(X=x) = {2c, 3c, 4c} where x= {-1, 1, 2} for 2c, 3c and 4c respectively.<BR>\n" );
document.write( "i. Find the value of c<BR>\n" );
document.write( "ii. Compute P(X = −1)<BR>\n" );
document.write( "iii. Find the standard deviation of X<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 #814736 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=814736\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <BR>\n" );
document.write( "The sum of the probabilities for all the x values must be 1 --\r<BR>\n" );
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document.write( "i.   2c + 3c + 4c = 9c = 1 ===> c = 1/9.\r<BR>\n" );
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document.write( "ii.   <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=P%28X+=+-1%29+=+2%2F9 ALIGN=MIDDLE  ALT=\"P%28X+=+-1%29+=+2%2F9\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "iii.  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=mu+=+%28-1%29%2A%282%2F9%29+%2B+1%2A%283%2F9%29+%2B+2%2A%284%2F9%29+=+9%2F9+=+1 ALIGN=MIDDLE  ALT=\"mu+=+%28-1%29%2A%282%2F9%29+%2B+1%2A%283%2F9%29+%2B+2%2A%284%2F9%29+=+9%2F9+=+1\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=E%28X%5E2%29+=+%28-1%29%5E2%2A%282%2F9%29+%2B+1%5E2%2A%283%2F9%29+%2B+2%5E2%2A%284%2F9%29+=+21%2F9+=+7%2F3 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "===> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=sigma%5E2+=+E%28X%5E2%29+-+mu%5E2+=+7%2F3+-+1%5E2+=+4%2F3 ALIGN=MIDDLE  ALT=\"sigma%5E2+=+E%28X%5E2%29+-+mu%5E2+=+7%2F3+-+1%5E2+=+4%2F3\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "===> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=highlight%28sigma+=+2%2Fsqrt%283%29%29 ALIGN=MIDDLE  ALT=\"highlight%28sigma+=+2%2Fsqrt%283%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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