document.write( "Question 1171181: Suppose that 20% of the college seniors support an increase in federal funding for care of
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Algebra.Com's Answer #796102 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "It is a binomial distribution type problem, where the probability under the question is the sum\r\n" );
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document.write( "     P = P(at most 3) = P(0) + P(1) + P(2) + P(3) =       (1)\r\n" );
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document.write( "The number of trials is              20;\r\n" );
document.write( "The indexes of success trials        k = 0,1,2,3\r\n" );
document.write( "The probability of success trial     p = 0.2;\r\n" );
document.write( "                                     q = 1 - p\r\n" );
document.write( "C(n,k) = n! / (k! * (n-k)!)          are binomial coefficients.\r\n" );
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document.write( "The sum  (1)  is a cumulative sum.\r\n" );
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document.write( "Instead of calculating every term of (1) individually and then summing them up, you may use Excel function \r\n" );
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document.write( "BINOM.DIST(3, 20, 0.2, TRUE)  to calculate the cumulative sum value in one click.\r\n" );
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document.write( "In this way,  you get\r\n" );
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document.write( "    P =  = 0.411449.      ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "On Excel function BINOM.DIST, see its description everywhere, for example\r
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\n" ); document.write( "\n" ); document.write( "On binompdf function for pocket calculators TI-83 and TI-84 see the link\r
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\n" ); document.write( "\n" ); document.write( "If you want to see other similar solved problems, look into the lessons\r
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