document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=959161>Question 959161</A>: <I><SPAN STYLE=\"word-break: break-all;\"> if the probability of getting a lift to work  on any morning is  0.6 .X is the number of days in a working  week of 5 days\r<BR>\n" );
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document.write( "(a) what is the probability  distribution of X? (please justify)<BR>\n" );
document.write( "(b) what is the probability  that in a working week will get a lift only twice? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #586297 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=586297\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> if the probability of getting a lift to work on any morning is 0.6 .X is the number of days in a working week of 5 days<BR>\n" );
document.write( " (a) what is the probability distribution of X? (please justify)<BR>\n" );
document.write( "mean = np = 5*0.6 = 3<BR>\n" );
document.write( "std = sqrt(npq) = sqrt(3*0.4) = sqrt(1.2)<BR>\n" );
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document.write( " (b) what is the probability that in a working week will get a lift only twice?<BR>\n" );
document.write( "P(x = 2) = 5C2*0.6^2*0.4^3 = binompdf(5,0.6,2) = 0.2304<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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