document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1153795>Question 1153795</A>: <I><SPAN STYLE=\"word-break: break-all;\"> A box contain 74 brass watchers 86 steel watchers and 40 aluminum watchers three watchers drawn at random from the box without replacement determine the probability that no aluminum watchers are drawn at random from the box without replacement\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 #776086 by </B><A HREF=/tutors/aboutme.mpl?userid=greenestamps><B>greenestamps(13200)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=greenestamps><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=greenestamps><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=776086\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> <br><BR>\n" );
document.write( "washers, not watchers....!<br><BR>\n" );
document.write( "Number of ways of choosing 3 of the total 160 washers: C(160,3) = 669920<br><BR>\n" );
document.write( "Number of ways of choosing 3 that are not aluminum -- i.e., choosing 3 of the 120 washers that are not aluminum: C(120,3) = 280840<br><BR>\n" );
document.write( "Probability of choosing 3 of which none are aluminum:<br><BR>\n" );
document.write( "280840/669920 = .4192142345<br><BR>\n" );
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document.write( "P(1st is not aluminum) = 120/160 = 3/4<BR>\n" );
document.write( "P(2nd is not aluminum) = 119/159<BR>\n" );
document.write( "P(3rd is not aluminum) = 118/158 = 59/79<br><BR>\n" );
document.write( "P(all 3 are not aluminum) = (3/4)(119/59)(59/79) = 21063/50244 = .4192142345<br> <BR>\n" );
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