document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=442721>Question 442721</A>: <I><SPAN STYLE=\"word-break: break-all;\"> How do I know the differences between P(A OR B) and P(A and B)?????? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #305399 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=305399\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Ok, so for P(A or B), if either P(A) happens or P(B) happens, then the outcome is true. So, we can write P(A or B) as  P(A) + P(B) if we are mutually exclusive.\r<BR>\n" );
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document.write( "If we are not mutually exclusive, we have to take away the probability of both A and B happening. So P(A or B) is  P(A) + P(B) - P(A and B).\r<BR>\n" );
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document.write( "Now for P(A and B), both A and B have to happen for the outcome to be true. So we have to account for the probability of A and then account for the probability of B. P(A and B) = P(A) * P(B). Provided that A has already happened.\r<BR>\n" );
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document.write( "Say you have a coin. The first time you flip it you have a 1/2 probability of getting heads. Let's say you flip it again, you still have a 1/2 probability of getting heads. As you add more probabilities, the ultimate probability is going to become slimmer and slimmer. In this case, you have a 1/4 chance of flipping heads 2 times.  </SPAN>\n" );
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