A Statistics Department Is Contacting Alumni by Telephone Asking for Donations

Short Answer

A Statistics Department is contacting alumni by telephone asking for donations to help fund a new computer laboratory. Past history shows that 80% of the alumni contacted in this manner will make a contribution of at least $50. A random sample of 20 alumni is selected. Let x represent number of alumni that makes at contribution of at least $50.
What is the probability that exactly 15 alumni will make a contribution of at least $50?
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What is the probability that between 14 and 18 alumni, inclusively, will make a contribution of at least $50?
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What is the probability that less than 17 alumni will make a contribution of at least $50?
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What is the probability that more than 15 alumni will make a contribution of at least $50?
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How many alumni would you expect to make a contribution of at least $50?
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