document.write( "Question 877978: Help please - I have tried to use the Binominal Distribution formula to solve this question but I think the wording is confusing me and I am using the wrong values. Maybe I need to use the Hypergeometric or Poisson - very confused.
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\n" ); document.write( "Here is the question: A company reserved 20 rooms for a training class at a hotel that advertised \"99% of our guests are delighted with their stay!\" Surveys showed that 2 of the attendees were dissatisfied with the hotel. What is the probability that 2 or more guests would be dissatisfied if the hotel's advertising claim was true?
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Algebra.Com's Answer #529650 by Edwin McCravy(20056)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Yes, that's a binomial problem.  The probability that there are 19 or\r\n" );
document.write( "fewer successes out of 20 trials, where the probability of success in ONE\r\n" );
document.write( "trial is .99\r\n" );
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document.write( "n = 20 trials\r\n" );
document.write( "p = .01 = probability of 1 \"success\" in 1 trial.\r\n" );
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document.write( "Note: Here a \"success\" is that a person would be satisfied.\r\n" );
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document.write( "x <= 19\r\n" );
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document.write( "With my TI-84\r\n" );
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document.write( "Press ON\r\n" );
document.write( "Press CLEAR\r\n" );
document.write( "Press 2ND\r\n" );
document.write( "Press VARS\r\n" );
document.write( "Use down arrow key to scroll to B:binomcdf(\r\n" );
document.write( "Press ENTER\r\n" );
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document.write( "Depending on how old your calculator is or what mode it is in,\r\n" );
document.write( "you may see this:\r\n" );
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document.write( "                         binomcdf\r\n" );
document.write( "                      trials:\r\n" );
document.write( "                      p:\r\n" );
document.write( "                      x value\r\n" );
document.write( "                      Paste\r\n" );
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document.write( "If so make it read      binomcdf\r\n" );
document.write( "                      trials:20\r\n" );
document.write( "                      p:.99\r\n" );
document.write( "                      x value:19\r\n" );
document.write( "                      Paste\r\n" );
document.write( "\r\n" );
document.write( "Highlight Paste\r\n" );
document.write( "Press ENTER\r\n" );
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document.write( "You'll see:  \r\n" );
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document.write( "binomcdf(20,.99,\r\n" );
document.write( "19)\r\n" );
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document.write( "Or if you have an old TI-84 see binomcdf(\r\n" );
document.write( "Make it read \r\n" );
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document.write( "binomcdf(20,.99,\r\n" );
document.write( "19)\r\n" );
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document.write( "Press ENTER   \r\n" );
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document.write( "You'll see .0010035762\r\n" );
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document.write( "Edwin

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