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        riddles >> easy >> Phone Directory
        
(Message started by: maryl on Jul 8^th, 2003, 1:56pm)

Title: Phone Directory
Post by maryl on Jul 8^th, 2003, 1:56pm

There is a town in Texas where 5% of all the people living there have unlisted phone numbers. If you selected 100 names at random from the town's phone directory, on average, how many of these people would have unlisted phone numbers?

Title: Re: Phone Directory
Post by Leonid Broukhis on Jul 8^th, 2003, 2:08pm

[hide]Zero[/hide], if it is a public phone directory, and [hide]5[/hide] if it is a classified phone directory.

Title: Re: Phone Directory
Post by Lupin on Jul 15^th, 2003, 4:15pm

I know is a "gotcha" but ... [HIDE]people who have unlisted phone numbers may as well also have regular phone numbers and vice-versa[/HIDE]