document.write( "Question 1202102: the probability of winning is 0.2. the least number of games that must be played to ensure the probability of winning two prize is more than 0.95 \n" ); document.write( "
Algebra.Com's Answer #836759 by Edwin McCravy(20067)\"\" \"About 
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document.write( "To have won two prizes in n trials is the same as failing to win fewer than n-2\r\n" );
document.write( "times in n trials.\r\n" );
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document.write( "By my TI-84, binomcdf(21,0.8,19) gives 0.9423539248 which is not quite 0.95\r\n" );
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document.write( "but binomcdf(22,0.8,20) gives 0.9520384654\r\n" );
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document.write( "So the answer is 22.\r\n" );
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document.write( "Edwin
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