50 to 1 odds

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50 to 1 odds
Message posted by Farres (via 198.135.203.6) on September 17, 2001 at 6:59 PM (ET)

I'm writing a story that deals with someone sending in an application to attend an event on a particular day. The published odds of being successfully selected to attend the event via random-computer drawing is 51.7 to one. Only one application per person per event date is allowed. If a person sends in 10 single applications for 10 different dates, what are their odds of being successfully selected? Thanks to all who reply.

READERS RESPOND:
(In chronological order. Most recent at the bottom.)

Re: 50 to 1 odds
Message posted by Jack Tomsky (via 208.249.113.130) on September 17, 2001 at 7:37 PM (ET)

I'm assuming that you really mean that the odds "against" being selected for a single event are 51.7 to one. In that case, the probability of being successfully selected for at least one event out of ten is one minus the probability of being rejected all ten times. Thus,

P = 1-(51.7/52.7)^10 = 0.174.

Re: 50 to 1 odds
Message posted by Farres (via 198.135.203.6) on September 18, 2001 at 12:24 PM (ET)

Jack-
Thanks for your reply. I'm far from a math wiz, so I would appreciate it if you would break it down or explain it a little further. Are you saying the odds improve slightly or remain the same? Apologies for being dense, but my college stats classes are a fading memory. Thanks again.

Re: 50 to 1 odds
Message posted by Jack Tomsky (via 208.249.113.130) on September 18, 2001 at 1:23 PM (ET)

Faress, the probability of being selected at least once goes up (not quite tenfold) since the applicant has ten tries at being selected. I hope this helps.

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