document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=668497>Question 668497</A>: <I><SPAN STYLE=\"word-break: break-all;\"> 1. A class tossed coins and recorded 161 heads and 179 tails. What is the experimental probability of heads? Of tails?\r<BR>\n" );
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document.write( "2. If you guess the answers at random, what is the probability of getting at least three correct answers on a five question true-or-false quiz.<BR>\n" );
document.write( "NOTE: We reviewed both problems in class. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #415624 by </B><A HREF=/tutors/aboutme.mpl?userid=swincher4391><B>swincher4391(1107)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=swincher4391><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=swincher4391><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=415624\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> P(heads) = 161/(161+179) = 161/340<BR>\n" );
document.write( "P(tails) = 179/(161+179) = 179/340\r<BR>\n" );
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document.write( "P(at least three correct answers) = P(three)+ P(four) + P(five) = (5 choose 3) * (1/2)^3 *(1/2)^2 + (5 choose 4) *(1/2)^4 * (1/2)^1 + (5 choose 5) * (1/2)^5 * (1/2)^0 =  1/2 </SPAN>\n" );
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