document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1167136>Question 1167136</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The random variable X represents the number of tests that a patient entering a hospital will have along with the corresponding probabilities. Find the mean and variance.\r<BR>\n" );
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document.write( "X	0	1	2	3	4<BR>\n" );
document.write( "P(X=x)	0.21	0.19	0.32	0.17	0.11\r<BR>\n" );
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document.write( "Calculate the following.\r<BR>\n" );
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document.write( "(a)P(1 ≤ X ≤ 3)<BR>\n" );
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document.write( "(b)Variance of random variable 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 #791753 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=791753\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> mean is x*p(x)=0+0.19+0.64+0.51+0.44<BR>\n" );
document.write( "=1.78<BR>\n" );
document.write( "variance is sum of the squared deviations or<BR>\n" );
document.write( " 1.78^2*0.21=0.665<BR>\n" );
document.write( "0.78^2*0.19=0.116<BR>\n" );
document.write( "0.22^2*0.32=0.015<BR>\n" );
document.write( "1.22^2*0.17=0.253<BR>\n" );
document.write( "2.22^2*0.11=0.542\r<BR>\n" );
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document.write( "the sum is 1.591\r<BR>\n" );
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document.write( "between 1 and 3 has probability of 0.68\r<BR>\n" );
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