document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1070161>Question 1070161</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Dear Math Expert , can you help me with this problem :)<BR>\n" );
document.write( " Three distinct integers are chosen at random from the first 20 positive integers compute the probability that<BR>\n" );
document.write( "a- their sum is even<BR>\n" );
document.write( "b- their product is even  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #685276 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=685276\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Three distinct integers are chosen at random from the first 20 positive integers compute the probability that<BR>\n" );
document.write( "a- their sum is even::: <BR>\n" );
document.write( "all three are even:: 10C3 = 120<BR>\n" );
document.write( "2 are odd and one is even:: 10C2*10 = 450<BR>\n" );
document.write( "P(sum is even) = (120+450)/20C3 = 370/1140 = 37/114<BR>\n" );
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document.write( "b- their product is even <BR>\n" );
document.write( "all three are odd:: 10C3 = 120<BR>\n" );
document.write( "----<BR>\n" );
document.write( "P(product is even) = (20C3-120)/20C3 = 1020/1140 =  51/57 = 17/19<BR>\n" );
document.write( "------------<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( "</TD></TR></TABLE>\n" );