document.write( "Question 1206645: Suppose that about 85% of graduating students attend their graduation. A group of 21 graduating students is randomly chosen.
\n" ); document.write( "In words, define the Random Variable X.
\n" ); document.write( "the number of graduating students that attend graduation
\n" ); document.write( "the number of people attending graduation
\n" ); document.write( "the number of graduating students that are not attending graduation
\n" ); document.write( "the number of graduates
\n" ); document.write( "List the values that X may take on.
\n" ); document.write( "X = 1, 2, 3, . . ., 19, 20, 21
\n" ); document.write( "X = 0, 1, 2, . . ., 83, 84, 85
\n" ); document.write( "X = 0, 1, 2, . . ., 19, 20, 21
\n" ); document.write( "X = 1, 2, 3, . . ., 83, 84, 85
\n" ); document.write( "Give the distribution of X.
\n" ); document.write( "How many students are expected to attend their graduation? (Round your answer to the nearest whole number.)
\n" ); document.write( "Find the probability that 17 or 18 attend. (Round your answer to four decimal places.)
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Algebra.Com's Answer #844232 by ikleyn(52805)\"\" \"About 
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\n" ); document.write( "Suppose that about 85% of graduating students attend their graduation. A group of 21 graduating students is randomly chosen.
\n" ); document.write( "(a) In words, define the Random Variable X.
\n" ); document.write( "the number of graduating students that attend graduation
\n" ); document.write( "the number of people attending graduation
\n" ); document.write( "the number of graduating students that are not attending graduation
\n" ); document.write( "the number of graduates
\n" ); document.write( "(b) List the values that X may take on.
\n" ); document.write( "X = 1, 2, 3, . . ., 19, 20, 21
\n" ); document.write( "X = 0, 1, 2, . . ., 83, 84, 85
\n" ); document.write( "X = 0, 1, 2, . . ., 19, 20, 21
\n" ); document.write( "X = 1, 2, 3, . . ., 83, 84, 85
\n" ); document.write( "(c) Give the distribution of X.
\n" ); document.write( "(d) How many students are expected to attend their graduation? (Round your answer to the nearest whole number.)
\n" ); document.write( "(e) Find the probability that 17 or 18 attend. (Round your answer to four decimal places.)
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document.write( "(a)  In words, define the Random Variable X.\r\n" );
document.write( "     the number of graduating students that attend graduation              <<<---===\r\n" );
document.write( "     the number of people attending graduation\r\n" );
document.write( "     the number of graduating students that are not attending graduation\r\n" );
document.write( "     the number of graduates\r\n" );
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document.write( "(b)  List the values that X may take on.\r\n" );
document.write( "     X = 1, 2, 3, . . ., 19, 20, 21\r\n" );
document.write( "     X = 0, 1, 2, . . ., 83, 84, 85\r\n" );
document.write( "     X = 0, 1, 2, . . ., 19, 20, 21   <<<---===\r\n" );
document.write( "     X = 1, 2, 3, . . ., 83, 84, 85\r\n" );
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document.write( "(c)  It is the binomial distribution with n= 21 trials and p= 0.85 the probability\r\n" );
document.write( "     of success for each individual trial.\r\n" );
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document.write( "(d)  \"how many students are expected\" is the mathematical expectation.\r\n" );
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document.write( "      For a binomial distribution it is  E = n*p = 21*0.85 = 17.85,\r\n" );
document.write( "                                                   or 18, rounded to the closest integer.\r\n" );
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document.write( "(e)  To find P(17 or 18), use the standard formula of binomial distribution\r\n" );
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document.write( "     P(17 or 18) =  = \"5985%2A0.85%5E17%2A0.15%5E4+%2B+1330%2A0.85%5E18%2A0.15%5E3\" = 0.4320  (rounded).\r\n" );
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