document.write( "Question 262826: I don't even know how to set up this problem. I am not finding examples, can you help please? \r
\n" ); document.write( "\n" ); document.write( "Events A and B are mutually exclusive events defined on a common sample space. If P (A) = 0.3
\n" ); document.write( "and P(A or B) = 0.75, find P(B).
\n" ); document.write( "(B) Events A and B are defined on a common sample space. If P(A) = 0.30, P(B) = 0.50, and P(A or
\n" ); document.write( "B) = 0.72, find P(A and B)
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Algebra.Com's Answer #193595 by drk(1908)\"\" \"About 
You can put this solution on YOUR website!
We have a general formula to help us:
\n" ); document.write( "(i) \"p%28A+u+B%29+=+p%28A%29+%2B+p%28B%29+-+p%28A+n+B%29\"
\n" ); document.write( "p(a u B) means probability of A union B. Union is another word for \"OR\"
\n" ); document.write( "p(A n B) means probability of A intersection B. Intersection is another word for \"AND\"
\n" ); document.write( "since events A and B are mutually exclusive, there will be no overlap and there fore, p(A n B) = 0.
\n" ); document.write( "From above and this information, we get
\n" ); document.write( "(ii) \".75+=+.3+%2B+p%28B%29+%2B+0\"
\n" ); document.write( "solving for p(B), we get
\n" ); document.write( "(iii) \"p%28B%29+=+.45\"
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\n" ); document.write( "part (B):
\n" ); document.write( "using the same formula as
\n" ); document.write( "(iv) \"p%28A+u+B%29+=+p%28A%29+%2B+p%28B%29+-+p%28A+n+B%29\"
\n" ); document.write( "and the given information, we get
\n" ); document.write( "(i) \".72+=+.30+%2B+.50+-+p%28A+n+B%29\"
\n" ); document.write( "we get
\n" ); document.write( "\"p%28A+n+B%29+=+.08\"
\n" ); document.write( "this means there is a slight overlap of the 2 sets.
\n" ); document.write( "hope this helps.
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