document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=86613>Question 86613</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I need help with these problems if someone has time to help me explain them to me step by steps thanks.\r<BR>\n" );
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document.write( "Problem #1<BR>\n" );
document.write( "Breast Cancer To explain why the chance of a woman<BR>\n" );
document.write( "getting breast cancer in the next year goes up each year,<BR>\n" );
document.write( "while the chance of a woman getting breast cancer in her<BR>\n" );
document.write( "lifetime goes down, Ruma Falk made the following analogy.†<BR>\n" );
document.write( "Suppose you are looking for a letter that you may<BR>\n" );
document.write( "have lost.You have 8 drawers in your desk. There is a probability<BR>\n" );
document.write( "of .1 that the letter is in any one of the 8 drawers,<BR>\n" );
document.write( "and a probability of .2 that the letter is not in any of the<BR>\n" );
document.write( "drawers.<BR>\n" );
document.write( "a. What is the probability that the letter is in drawer 1?<BR>\n" );
document.write( "b. Given that the letter is not in drawer 1, what is the probability<BR>\n" );
document.write( "that the letter is in drawer 2?<BR>\n" );
document.write( "c. Given that the letter is not in drawer 1 or 2, what is the<BR>\n" );
document.write( "probability that the letter is in drawer 3?<BR>\n" );
document.write( "d. Given that the letter is not in drawers 1–7, what is the<BR>\n" );
document.write( "probability that the letter is in drawer 8?<BR>\n" );
document.write( "e. Based on your answers to parts a–d, what is happening<BR>\n" );
document.write( "to the probability that the letter is in the next drawer?<BR>\n" );
document.write( "f. What is the probability that the letter is in some drawer?<BR>\n" );
document.write( "g. Given that the letter is not in drawer 1, what is the probability<BR>\n" );
document.write( "that the letter is in some drawer?<BR>\n" );
document.write( "h. Given that the letter is not in drawer 1 or 2, what is the<BR>\n" );
document.write( "probability that the letter is in some drawer?<BR>\n" );
document.write( "i. Given that the letter is not in drawers 1–7, what is the<BR>\n" );
document.write( "probability that the letter is in some drawer?<BR>\n" );
document.write( "j. Based on your answers to parts f–i, what is happening to<BR>\n" );
document.write( "the probability that the letter is in some drawer?<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 #62655 by </B><A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><B>Edwin McCravy(20056)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Edwin+McCravy><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=Edwin+McCravy><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=62655\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <PRE STYLE=\"white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;\"><font size = 4><b>\r\n" );
document.write( "Suppose you are looking for a letter that you may\r\n" );
document.write( "have lost.You have 8 drawers in your desk. There is a probability\r\n" );
document.write( "of .1 that the letter is in any one of the 8 drawers,\r\n" );
document.write( "and a probability of .2 that the letter is not in any of the\r\n" );
document.write( "drawers.\r\n" );
document.write( "a. What is the probability that the letter is in drawer 1?\r\n" );
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document.write( "P(1 or 2 or ... or 8) = .1\r\n" );
document.write( "P(1)+P(2)+ ... + P(8) = .1\r\n" );
document.write( "P(1)=P(2)= ... =P(8) = .1/8 = 1/80 \r\n" );
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document.write( "b. Given that the letter is not in drawer 1, what is the probability\r\n" );
document.write( "that the letter is in drawer 2?\r\n" );
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document.write( "P(2 or 3 or ... or 8) = .1\r\n" );
document.write( "P(2)+P(3)+ ... + P(8) = .1\r\n" );
document.write( "P(2)=P(3)= ... =P(8) = .1/7 = 1/70\r\n" );
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document.write( "c. Given that the letter is not in drawer 1 or 2, what is the\r\n" );
document.write( "probability that the letter is in drawer 3?\r\n" );
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document.write( "P(3 or 4 or ... or 8) = .1\r\n" );
document.write( "P(3)+P(4)+ ... + P(8) = .1\r\n" );
document.write( "P(3)=P(4)= ... =P(8) = .1/6 = 1/60\r\n" );
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document.write( "d. Given that the letter is not in drawers 1–7, what is the\r\n" );
document.write( "probability that the letter is in drawer 8?\r\n" );
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document.write( "P(8) = .1\r\n" );
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document.write( "e. Based on your answers to parts a–d, what is happening\r\n" );
document.write( "to the probability that the letter is in the next drawer?\r\n" );
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document.write( "It's denominator is decreasing by 10, which means the\r\n" );
document.write( "probability is increasing.\r\n" );
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document.write( "f. What is the probability that the letter is in some drawer?\r\n" );
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document.write( "1 - P(not in any drawer) = 1 - .2 = .8\r\n" );
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document.write( "g. Given that the letter is not in drawer 1, what is the probability\r\n" );
document.write( "that the letter is in some drawer?\r\n" );
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document.write( "It's still .8\r\n" );
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document.write( "h. Given that the letter is not in drawer 1 or 2, what is the\r\n" );
document.write( "probability that the letter is in some drawer?\r\n" );
document.write( "\r\n" );
document.write( "It's still .8\r\n" );
document.write( "\r\n" );
document.write( "i. Given that the letter is not in drawers 1–7, what is the\r\n" );
document.write( "probability that the letter is in some drawer?\r\n" );
document.write( "\r\n" );
document.write( "It's still .8\r\n" );
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document.write( "j. Based on your answers to parts f–i, what is happening to\r\n" );
document.write( "the probability that the letter is in some drawer?\r\n" );
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document.write( "It's not changing, but staying .8.\r\n" );
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document.write( "Edwin</PRE> </SPAN>\n" );
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