document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=715167>Question 715167</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Jeanie is a bit forgetful, and if she doesn't make a \"to do\" list, the probability that she forgets something she is supposed to do is .5. Tomorrow she intends to run three errands, and she fails to write them on her list.<BR>\n" );
document.write( "(a) What is the probability that Jeanie forgets all three errands?\r<BR>\n" );
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document.write( "What assumptions did you make to calculate this probability?<BR>\n" );
document.write( "Events are .\r<BR>\n" );
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document.write( "(b) What is the probability that Jeanie remembers at least one of the three errands?\r<BR>\n" );
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document.write( "(c) What is the probability that Jeanie remembers the first errand but not the second or third?<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 #439308 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=439308\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Jeanie is a bit forgetful, and if she doesn't make a \"to do\" list, the probability that she forgets something she is supposed to do is .5. Tomorrow she intends to run three errands, and she fails to write them on her list.<BR>\n" );
document.write( "(a) What is the probability that Jeanie forgets all three errands?<BR>\n" );
document.write( "Ans: P(x = 0) = 0.5^3 = 0.125<BR>\n" );
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document.write( "What assumptions did you make to calculate this probability?<BR>\n" );
document.write( "Events are independent<BR>\n" );
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document.write( "(b) What is the probability that Jeanie remembers at least one of the three errands?<BR>\n" );
document.write( "P(1<= x <=3) = 1 - P(x = 0) = 1 - 0.125 = 0.875<BR>\n" );
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document.write( "(c) What is the probability that Jeanie remembers the first errand but not the second or third?<BR>\n" );
document.write( "P(yes,no,no) = (0.5)(0.5)(0.5) = 0.125<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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