document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1042771>Question 1042771</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A salesperson has a policy of calling upon a customer a second time if she does not make the sale on the first call, and trying a third time, and last time if she fails on the first two calls. She has a probability of a sale on the first call of 0.3. If she fails on the first call, the probability of a sale on the second call is 0.2. If the first two calls are unsuccessful, her probability of success on the third call is only 0.1.<BR>\n" );
document.write( "how i want do tree diagram for this question? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #658184 by </B><A HREF=/tutors/aboutme.mpl?userid=mathmate><B>mathmate(429)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=mathmate><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=mathmate><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=658184\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Question:<BR>\n" );
document.write( "A salesperson has a policy of calling upon a customer a second time if she does not make the sale on the first call, and trying a third time, and last time if she fails on the first two calls. She has a probability of a sale on the first call of 0.3. If she fails on the first call, the probability of a sale on the second call is 0.2. If the first two calls are unsuccessful, her probability of success on the third call is only 0.1.<BR>\n" );
document.write( "how i want do tree diagram for this question?<BR>\n" );
document.write( " <BR>\n" );
document.write( "Answer:<BR>\n" );
document.write( "The tree diagram is shown below.<BR>\n" );
document.write( "It is as important to understand how to interpret a tree-diagram as to draw it.<BR>\n" );
document.write( "The probability of failure is the product of probabilities of all three steps, namely<BR>\n" );
document.write( "P(failure)=0.7*0.8*0.9=0.504<BR>\n" );
document.write( "The probability of success, however, is the sum of three possible cases, depending on the number of calls made.<BR>\n" );
document.write( "P(success on first call)=0.3=0.300<BR>\n" );
document.write( "P(success on second call)=0.7*0.2=0.140<BR>\n" );
document.write( "P(success on third call)=0.7*0.8*0.1=0.056<BR>\n" );
document.write( "So total probability of success<BR>\n" );
document.write( "P(success)=0.300+0.140+0.056=0.496<BR>\n" );
document.write( "which is complementary to P(failure), or<BR>\n" );
document.write( "P(success)+P(failure)= 1.000<BR>\n" );
document.write( "is a good check for the ansewr.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=\"/cgi-bin/display-illustration.mpl?tutor=mathmate&illustration_name=tree\">. </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );