document.write( "Question 267846: Suppose there is a 69 percent chance that there will be traffic congestion on Bridge A, a 57 percent chance there will be traffic congestion on bridge B, and a 45 percent chance there will be traffic on both bridges. what is the probability that there will be traffic congestion on AT LEAST one bridge? \n" ); document.write( "
Algebra.Com's Answer #196460 by stanbon(75887)\"\" \"About 
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Suppose there is a 69 percent chance that there will be traffic congestion on Bridge A, a 57 percent chance there will be traffic congestion on bridge B, and a 45 percent chance there will be traffic on both bridges. what is the probability that there will be traffic congestion on AT LEAST one bridge?
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\n" ); document.write( "P(A jam) = 0.69
\n" ); document.write( "P(B jam) = 0.57
\n" ); document.write( "P(A and B) = 0.45
\n" ); document.write( "---
\n" ); document.write( "P(jam on at least one) = 1 - P(jam on none)
\n" ); document.write( "P(jam on none) = P(A' and B')
\n" ); document.write( "----
\n" ); document.write( "P(A' and B') = P(A') + P(B') - P(A' or B')
\n" ); document.write( "P(A' or B') = 1-P(A and B)
\n" ); document.write( "-----
\n" ); document.write( "So P(A' and B') = 0.31 + 0.43 -[1-0.45]
\n" ); document.write( "= 0.74 - 0.55
\n" ); document.write( "= 0.19
\n" ); document.write( "------------
\n" ); document.write( "Therefore P(jam on at least one) = 1-0.19 = 0.81
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\n" ); document.write( "cheers,
\n" ); document.write( "Stan H.
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\n" ); document.write( "\n" ); document.write( "P(jam on at least one) = 1 - P(jam on none)
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