Hotels, Like Airlines, Often Overbook, Counting on the Fact That

Short Answer

Hotels, like airlines, often overbook, counting on the fact that some people with reservations will cancel at the last minute. A certain hotel chain finds 20% of the reservations will not be used.
If we randomly selected 15 reservations, what is the probability more than 8 but less than 12 reservations will be used?
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If four reservations are made, what is the chance fewer than two will cancel?
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