document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1195011>Question 1195011</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In an urn there are 3 white and 4 black marbles. They are taken out of the urn one by one. What is the chance of the first and last marble being white? </SPAN>\n" );
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document.write( "The total number of ways of arranging 3 white marbles and 4 black marbles is<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%283%2B4%29%21%2F%28%283%21%29%284%21%29%29+=+35 ALIGN=MIDDLE  ALT=\"%283%2B4%29%21%2F%28%283%21%29%284%21%29%29+=+35\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "With white marbles in the first and last positions, the number of ways of arranging the remaining 1 white marble and 4 black marbles is<br><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%281%2B4%29%21%2F%28%281%21%29%284%21%29%29+=+5 ALIGN=MIDDLE  ALT=\"%281%2B4%29%21%2F%28%281%21%29%284%21%29%29+=+5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><br><BR>\n" );
document.write( "So the probability that the first and last marbles are both white is 5/35=1/7.<br><BR>\n" );
document.write( " </SPAN>\n" );
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