document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=465602>Question 465602</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 25.If the variance of a random variable X is given Var(X)=3. Then Var(2X)  is\r<BR>\n" );
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document.write( "30.The lifetime of a machine part has a continuous distribution on the interval (0, 40) with probability density function  . Calculate the probability that the lifetime of the machine part is less than 6.\r<BR>\n" );
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document.write( "31.The lifetime of a machine part has a continuous distribution on the interval (0, 40) with probability density function  . Calculate the probability that the lifetime of the machine part is less than 5. \r<BR>\n" );
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document.write( "32.If  Var(X)=2, find Var(-3X+4).\r<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 #319037 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=319037\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> 25.If the variance of a random variable X is given Var(X)=3. <BR>\n" );
document.write( "Then Var(2X) is 2^2*Var(x) = 4*3 = 12<BR>\n" );
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document.write( "30.The lifetime of a machine part has a continuous distribution on the interval (0, 40) with probability density function . Calculate the probability that the lifetime of the machine part is less than 6.<BR>\n" );
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document.write( "z(6) = (6-0)/40 = 0.15<BR>\n" );
document.write( "P(x < 6) = P(z < 0.15) = 0.5596<BR>\n" );
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document.write( "31.The lifetime of a machine part has a continuous distribution on the interval (0, 40) with probability density function . Calculate the probability that the lifetime of the machine part is less than 5.<BR>\n" );
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document.write( "Same procedure as above.<BR>\n" );
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document.write( "32.If Var(X)=2, <BR>\n" );
document.write( "find Var(-3X+4) = (-3)^2*Var(x) = 9*2 = 18<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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