document.write( "Question 1095453: It is known that P(A)=0.3, P(B)=0.6, P(A and B')= 0.1. Find the probability of P( A U B) \n" ); document.write( "
Algebra.Com's Answer #709967 by Edwin McCravy(20081)\"\" \"About 
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document.write( "Let x,y,z, and w be the probabilities of the 4 regions\r\n" );
document.write( "in the Venn diagram below:\r\n" );
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document.write( "P(A) = x+y = 0.3\r\n" );
document.write( "P(B) = y+z = 0.6\r\n" );
document.write( "P(A&B') = x = 0.1\r\n" );
document.write( "P(AUB) = x+y+z = ??\r\n" );
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document.write( "Since x = 0.1,\r\n" );
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document.write( "substitute 0.1 for x in x+y = 0.3\r\n" );
document.write( "                      0.1+y = 0.3\r\n" );
document.write( "                          y = 0.2\r\n" );
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document.write( "Substitute 0.2 for y in y+z = 0.6\r\n" );
document.write( "                      0.2+z = 0.6\r\n" );
document.write( "                          z = 0.4\r\n" );
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document.write( " P(AUB) = x+y+z = 0.1+0.2+0.4 = 0.7   <--answer\r\n" );
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document.write( "It's also true that w = P(A'&B') = 1 - 0.7 = 0.3\r\n" );
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document.write( "Edwin

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