document.write( "Question 1201749: According to flightstats.com, American Airlines flights from Dallas to Chicago are on time 80% of the time. Suppose 15 flights are randomly selected, and the number of on-time flights is recorded.\r
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\n" ); document.write( "\n" ); document.write( "(a) Find the probability that exactly 11 flights are on time.
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\n" ); document.write( "\n" ); document.write( "(b) Find the probability that fewer than 11 flights are on time. \r
\n" ); document.write( "\n" ); document.write( "(c) Find the probability that at least 11 flights are on time. \r
\n" ); document.write( "\n" ); document.write( "(d) Find the probability that between 9 and 11 flights, inclusive, are on time. \r
\n" ); document.write( "\n" ); document.write( "(e) Compute the mean and standard deviation of the random variable X, the number of on-time flights in 15 trials of the probability experiment.\r
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Algebra.Com's Answer #836251 by ikleyn(52800)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "According to flightstats.com, American Airlines flights from Dallas to Chicago
\n" ); document.write( "are on time 80% of the time. Suppose 15 flights are randomly selected,
\n" ); document.write( "and the number of on-time flights is recorded.
\n" ); document.write( "Note: Write your answer rounded to four decimal places.
\n" ); document.write( "(a) Find the probability that exactly 11 flights are on time.
\n" ); document.write( "0.1136
\n" ); document.write( "(b) Find the probability that fewer than 11 flights are on time.
\n" ); document.write( "(c) Find the probability that at least 11 flights are on time.
\n" ); document.write( "(d) Find the probability that between 9 and 11 flights, inclusive, are on time.
\n" ); document.write( "(e) Compute the mean and standard deviation of the random variable X, the number of on-time flights in 15 trials of the probability experiment.
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\n" ); document.write( "\n" ); document.write( "            It is a typical binomial distribution probability problem.\r
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\n" ); document.write( "\n" ); document.write( "            Go to web-site https://stattrek.com/online-calculator/binomial.aspx\r
\n" ); document.write( "\n" ); document.write( "            and use free of charge online calculator there, specially developed for such problems.\r
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\n" ); document.write( "\n" ); document.write( "            The number of trials is n= 15; the probability p of each success individual trial is 0.8.\r
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document.write( "(a) p = P(n=15;  k=11; p=0.8) = 0.1876.\r\n" );
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document.write( "(b) p = P(n=15; k<11; p=0.8) = 0.16424.\r\n" );
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document.write( "(c) p = P(n=15; k>=11; p=0.8) = 0.83576.\r\n" );
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document.write( "(d) p = P(n=15; 9<= k <=11; p=0.8) = P(n=15; k<=11; p=0.8) - P(n=15; k<9; p=0.8) = 0.35184 - 0.01806 = 0.33378.\r\n" );
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document.write( "(e) Mean = n*p = 15*0.8 = 1.2\r\n" );
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document.write( "    SD = \"sqrt%28n%2Ap%2A%281-p%29%29\" = \"sqrt%2815%2A0.8%2A%281-0.8%29%29\" = 1.5492  (rounded).\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved, with all necessary explanations.\r
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\n" ); document.write( "\n" ); document.write( "To see a variety similar solved problems,  look into the lessons\r
\n" ); document.write( "\n" ); document.write( "    - Simple and simplest probability problems on Binomial distribution \r
\n" ); document.write( "\n" ); document.write( "    - Typical binomial distribution probability problems \r
\n" ); document.write( "\n" ); document.write( "    - How to calculate Binomial probabilities with Technology (using MS Excel) \r
\n" ); document.write( "\n" ); document.write( "    - Solving problems on Binomial distribution with Technology (using MS Excel) \r
\n" ); document.write( "\n" ); document.write( "    - Solving problems on Binomial distribution with Technology (using online solver) \r
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\n" ); document.write( "\n" ); document.write( "After reading these lessons,  you will be able to solve such problems on your own, \r
\n" ); document.write( "\n" ); document.write( "which is your  PRIMARY  MAJOR  GOAL  visiting this forum  (I believe).\r
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