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  • Question

  • In a large western city, 80% of the phone numbers are listed, 20% of the phone numbers are businesses, and 20% of the phone numbers start with the numeral "2". If you were to take a random sample of 1000 phone numbers from the city's phone book, how many numbers would you expect to be unlisted, non-business phone numbers that start with a numeral other than "2"?
    Wednesday, October 31, 2007 2:31 PM