document.write( "Question 1001201: Question from Binomial Probability
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document.write( "If three coins are tossed, find the probability of each number of heads.
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document.write( "4) 3
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document.write( "5) 1 or 2
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document.write( "6) at least 1\r
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document.write( "According to the book, For number 5 the answer is 3/4.
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document.write( "would like to see solutions shown for all three. Thanks.
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Algebra.Com's Answer #618443 by rothauserc(4718)![]() ![]() You can put this solution on YOUR website! The binomial probability formula is \n" ); document.write( "P(k successes in n trials) = nCk * p^k * q^(n-k) where \n" ); document.write( "n = number of trials \n" ); document.write( "k = number of successes \n" ); document.write( "n-k = number of failures \n" ); document.write( "p = probability of success in one trial \n" ); document.write( "q = 1 – p = probability of failure in one trial \n" ); document.write( "nCk = combination of n trials taken k at a time \n" ); document.write( "*************************************************************************** \n" ); document.write( "for our problem \n" ); document.write( "n = 3 \n" ); document.write( "p = 0.50 \n" ); document.write( "q = 0.50 \n" ); document.write( "*************************************************************************** \n" ); document.write( "4) 3 successes \n" ); document.write( "P(3 successes in 3 trials)= 3C3 * (0.50)^3 * (0.50)^(3-3) = \n" ); document.write( "(3! / (3! * (3-3)!) * (0.125) * 1 = \n" ); document.write( "0.125 \n" ); document.write( "*************************************************************************** \n" ); document.write( "5) first calculate \n" ); document.write( "P(0 successes in 3 trials) = 3C0 * (0.50)^0 * (0.50)^(3-0) = \n" ); document.write( "(3! / (0! * (3-0)!) * 1 * (0.125) = \n" ); document.write( "0.125 \n" ); document.write( "therefore \n" ); document.write( "P(1 or 2 successes in 3 trials) = 1 - (P(3 successes in 3 trials) + P(0 successes in 3 trials)) = \n" ); document.write( "1 - (0.125 + 0.125) = 0.75 = 3/4 \n" ); document.write( "**************************************************************************** \n" ); document.write( "6) note that \n" ); document.write( "P(at least 1 success in 3 trials) = 1 - P(0 successes in 3 trials) = \n" ); document.write( "1 - 0.125 = 0.875 \n" ); document.write( "**************************************************************************** \r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |