SOLUTION: 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

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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
Answer by Edwin McCravy(20067) About Me  (Show Source):
You can put this solution on YOUR website!
To have won two prizes in n trials is the same as failing to win fewer than n-2
times in n trials.

By my TI-84, binomcdf(21,0.8,19) gives 0.9423539248 which is not quite 0.95

but binomcdf(22,0.8,20) gives 0.9520384654

So the answer is 22.

Edwin