document.write( "Question 1195929: Four teams A, B, C, and D compete in a tournament, and exactly one of them will
\n" ); document.write( "win the tournament. Teams A and B have the same chance of winning the tournament. Team C is
\n" ); document.write( "twice as likely to win the tournament as team D. The probability that either team A or team C wins
\n" ); document.write( "the tournament is 0.6. Find the probabilities of each team winning the tournament.
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Algebra.Com's Answer #828551 by math_tutor2020(3817)\"\" \"About 
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\n" ); document.write( "P(A) = x
\n" ); document.write( "P(B) = x
\n" ); document.write( "P(C) = 2y
\n" ); document.write( "P(D) = y
\n" ); document.write( "These are the probabilities of each team winning the tournament
\n" ); document.write( "The values are such that \"0+%3C=+x+%3C=+1\" and \"0+%3C=+y+%3C=+1\"\r
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\n" ); document.write( "\n" ); document.write( "Those probabilities add to 1 since they represent 100% of all possible cases.
\n" ); document.write( "P(A)+P(B)+P(C)+P(D) = 1
\n" ); document.write( "x+x+2y+y = 1
\n" ); document.write( "2x+3y = 1\r
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\n" ); document.write( "\n" ); document.write( "The probability of team A or C winning is 0.6, so,
\n" ); document.write( "P(A or C) = P(A) + P(C) ... mutually exclusive
\n" ); document.write( "P(A or C) = 0.6
\n" ); document.write( "P(A) + P(C) = 0.6
\n" ); document.write( "x+2y = 0.6
\n" ); document.write( "x = -2y+0.6\r
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\n" ); document.write( "\n" ); document.write( "Apply substitution
\n" ); document.write( "2x+3y = 1
\n" ); document.write( "2( x )+3y = 1
\n" ); document.write( "2( -2y+0.6 )+3y = 1
\n" ); document.write( "-4y+1.2+3y = 1
\n" ); document.write( "-y+1.2 = 1
\n" ); document.write( "-y = 1-1.2
\n" ); document.write( "-y = -0.2
\n" ); document.write( "y = 0.2
\n" ); document.write( "Therefore, P(C) = 2*y = 2*0.2 = 0.4 and P(D) = y = 0.2\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "And,
\n" ); document.write( "x = -2y+0.6
\n" ); document.write( "x = -2(0.2)+0.6
\n" ); document.write( "x = -0.4+0.6
\n" ); document.write( "x = 0.2
\n" ); document.write( "which means P(A) = P(B) = x = 0.2\r
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\n" ); document.write( "\n" ); document.write( "Summary:
\n" ); document.write( "P(A) = 0.2
\n" ); document.write( "P(B) = 0.2
\n" ); document.write( "P(C) = 0.4
\n" ); document.write( "P(D) = 0.2\r
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\n" ); document.write( "\n" ); document.write( "Check:
\n" ); document.write( "P(A)+P(B)+P(C)+P(D) = 1
\n" ); document.write( "0.2+0.2+0.4+0.2 = 1
\n" ); document.write( "1 = 1
\n" ); document.write( "and,
\n" ); document.write( "P(A or C) = P(A) + P(C) = 0.2 + 0.4 = 0.6
\n" ); document.write( "The answers are confirmed.
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