In a certain city, 5% of all the persons in town have unlisted phone numbers. If you select 100 names at random from that city's phone directory, how many people selected will have unlisted phone numbers? -Riddles

In a certain city, 5% of all the persons in town have unlisted phone numbers. If you select 100 names at random from that city's phone directory, how many people selected will have unlisted phone numbers? -Riddles
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1 Answer

Answer :

None. If their names are in the phone directory, they do not have unlisted phone numbers!
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