document.write( "Question 253039: A city council consists of 7 males and 4 females. Two counsilors are selected at random to represent the city at an Elton John concert. what is the probability that\r
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document.write( "A. both councilors are male?
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document.write( "B. one councilor is a male and one a female?
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document.write( "C. at least one councilor is a female?\r
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Algebra.Com's Answer #185225 by palanisamy(496) ![]() You can put this solution on YOUR website! A city council consists of 7 males and 4 females. \n" ); document.write( "Total number of counsilors = 7+4 = 11 \n" ); document.write( "Two counsilors are selected at random \n" ); document.write( "Total number of ways of forming the committee= 11C2 \n" ); document.write( " = 11*10/2 \n" ); document.write( " =55 \n" ); document.write( "A) If both counsilors are males \n" ); document.write( " Out of 7 males 2 can be selected in 7C2 ways \n" ); document.write( " Number of favourable events = 7*6/2 = 21 \n" ); document.write( " Probability p(A) = 21/55 \n" ); document.write( "B)one councilor is a male and one a female \n" ); document.write( " Out of 7 males 1 can be selected in 7 ways and out of 4 females 1 can be selected in 4 ways. \n" ); document.write( " Number of favourable events = 7*4 = 28 \n" ); document.write( " Probability p(B) = 28/55 \n" ); document.write( "C). At least one councilor is a female \n" ); document.write( "There are two possibilities. \n" ); document.write( "one male and one female or 2 females. \n" ); document.write( "In the first case probability = 28/55 ...(1) \n" ); document.write( "In the second case, out of 4 females 2 can be selected in 4C2 ways. \n" ); document.write( "Number of favourable events = 4*3/2 = 6 \n" ); document.write( " Probability = 6/55 ...(2) \n" ); document.write( "The required probability that at least one councilor \n" ); document.write( " is a female = (28/55)+(6/55) \n" ); document.write( " = 34/55\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( " |