document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=14625>Question 14625</A>: <I><SPAN STYLE=\"word-break: break-all;\"> First of all, thaks for helping in advance...\r<BR>\n" );
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document.write( "Here's the problem\r<BR>\n" );
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document.write( "Suppose there are 10 items on a true-false test. The person taking the test does not read the questions; he just answers each question randomly. What is the probability of his guessing all answers correctly?\r<BR>\n" );
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document.write( "I ended up with 1/512...but I started this a while ago and now I've forgotten how I got to that. Any help would be great.<BR>\n" );
document.write( "Thanks,<BR>\n" );
document.write( "Liz </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #53415 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=53415\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The probability of getting one answer right is 1/2<BR>\n" );
document.write( "The probability of getting two right is 1/2 *1/2 = 1/2^2=1/4<BR>\n" );
document.write( "You multiply because the events are independent; what you do<BR>\n" );
document.write( "on one problem does not effect what you do on the next.<BR>\n" );
document.write( "The prob of get all 10 right is (1/2)^10 = 1/1024<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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